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This concludes our overview of high-level plotting with regard to the topic of the Grammar of Graphics in the Python (and especially matplotlib) world. Next we will look at high-level plotting examples in the context of a particular data set and various methods for analyzing trends in that data. Data analysis This next...
sns.set(style="darkgrid")
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
For the following sections we will be using the precipitation and temperature data for Saint Francis, Kansas, USA, from 1894 to 2013. You can obtain CSV files for weather stations that interest you from the United States Historical Climatology Network. Let's load the CSV data that's been prepared for us, using the Pand...
data_file = "../data/KS147093_0563_data_only.csv" data = pd.read_csv(data_file)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
This will have read the data in and instantiated a Pandas DataFrame object, converting the first row to column data:
data.columns
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Here's what the data set looks like (well, the first bit of it, anyway):
data.head()
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
We'd like to see the "Month" data as names rather than numbers, so let's update that (but let's create a copy of the original, in case we need it later). We will be using month numbers and names later, so we'll set those now as well.
data_raw = pd.read_csv(data_file) month_nums = list(range(1, 13)) month_lookup = {x: calendar.month_name[x] for x in month_nums} month_names = [x[1] for x in sorted(month_lookup.items())] data["Month"] = data["Month"].map(month_lookup) data.head()
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
That's better :-) We're going to make repeated use of some of this data more than others, so let's pull those bits out:
years = data["Year"].values temps_degrees = data["Mean Temperature (F)"].values precips_inches = data["Precipitation (in)"].values
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Let's confirm the date range we're working with:
years_min = data.get("Year").min() years_min years_max = data.get("Year").max() years_max
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Let's set get the maximum and minimum values for our mean temperature and precipitation data:
temp_max = data.get("Mean Temperature (F)").max() temp_max temp_min = data.get("Mean Temperature (F)").min() temp_min precip_max = data.get("Precipitation (in)").max() precip_max precip_min = data.get("Precipitation (in)").min() precip_min
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Next, we'll create a Pandas pivot table, providing us with a convenient view of our data (making some of our analysis tasks much easier). If we use our converted data frame here (the one where we updated month numbers to names), our table will have the data in alphabetical order by month. As such, we'll want to use the...
temps = data_raw.pivot("Month", "Year", "Mean Temperature (F)") temps.index = [calendar.month_name[x] for x in temps.index] temps
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Let's do the the same thing for precipitation:
precips = data_raw.pivot("Month", "Year", "Precipitation (in)") precips.index = [calendar.month_name[x] for x in precips.index] precips
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
We've extracted most of the data and views that we'll need for the following sections, which are: * Analysis of Temperature, 1894-2013 * Analysis of Precipitation, 1894-2013 We've got everything we need, now; let's get started! Analysis of Temperature, 1894-2013 We're going to be analyzing temperatures in this sectio...
temps_colors = ["#FCF8D4", "#FAEAB9", "#FAD873", "#FFA500", "#FF8C00", "#B22222"] sns.palplot(temps_colors) temps_cmap = mpl.colors.LinearSegmentedColormap.from_list("temp colors", temps_colors)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Now let's take a look at the temperature data we have:
sns.set(style="ticks") (figure, axes) = plt.subplots(figsize=(18,6)) scatter = axes.scatter(years, temps_degrees, s=100, color="0.5", alpha=0.5) axes.set_xlim([years_min, years_max]) axes.set_ylim([temp_min - 5, temp_max + 5]) axes.set_title("Mean Monthly Temperatures from 1894-2013\nSaint Francis, KS, USA", fontsize=...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Notice something? The banding around the minimum and maximum values looks to be trending upwards. The scatter plot makes it a bit hard to see, though. We're going to need to do some work to make sure we're not just seeing things. So what do we want to do? * get the maximum and minimum values for every year * find the...
def get_fit(series, m, b): x = series.index y = m * x + b return pd.Series(y, x) temps_max_x = temps.max().index temps_max_y = temps.max().values temps_min_x = temps.min().index temps_min_y = temps.min().values (temps_max_slope, temps_max_intercept, temps_max_r_value, temps_max_p_value, temps_max_std_...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Let's look at the slopes of the two:
(temps_max_slope, temps_min_slope)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Quick refresher: the slope $m$ is defined as the change in $y$ values over the change in $x$ values: \begin{align} m = \frac{\Delta y}{\Delta x} = \frac{\text{vertical} \, \text{change} }{\text{horizontal} \, \text{change} } \end{align} In our case, the $y$ values are the minimum and maximum mean monthly temperatures i...
temps_min_slope/temps_max_slope
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Let's go back to our scatter plot and superimpose our linear fits for the maximum and minimum annual means:
(figure, axes) = plt.subplots(figsize=(18,6)) scatter = axes.scatter(years, temps_degrees, s=100, color="0.5", alpha=0.5) temps_max_fit.plot(ax=axes, lw=5, color=temps_colors[5], alpha=0.7) temps_min_fit.plot(ax=axes, lw=5, color=temps_colors[3], alpha=0.7) axes.set_xlim([years_min, years_max]) axes.set_ylim([temp_min ...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
By looking at at the gaps above and below the min and max fits, it seems like there is a greater rise in the minimums. We can get a better visual, though, by superimposing the two lines. Let's remove the vertical distance and compare:
diff_1894 = temps_max_fit.iloc[0] - temps_min_fit.iloc[0] diff_2013 = temps_max_fit.iloc[-1] - temps_min_fit.iloc[-1] (diff_1894, diff_2013)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
So that's the difference between the high and low for 1894 and then the difference in 2013. As we can see, the trend over the last century for this one weather station has been a lessening in the difference between the maximum and minimum values. Let's shift the highs down by the difference in 2013 and compare the slop...
vert_shift = temps_max_fit - diff_2013 (figure, axes) = plt.subplots(figsize=(18,6)) vert_shift.plot(ax=axes, lw=5, color=temps_colors[5], alpha=0.7) temps_min_fit.plot(ax=axes, lw=5, color=temps_colors[3], alpha=0.7) axes.set_xlim([years_min, years_max]) axes.set_ylim([vert_shift.min() - 5, vert_shift.max() + 1]) axe...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Now you can see the difference! Let's tweak our seaborn style for the next set of plots we'll be doing:
sns.set(style="darkgrid")
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Seaborn offers some plots that are very useful when looking at lots of data: * heat maps * cluster maps (and the normalized variant) Let's use the first one next, to get a sense of what the means temperatures look like for each month over the course of the given century -- without any analysis, just a visualization o...
(figure, axes) = plt.subplots(figsize=(17,9)) axes.set_title(("Heat Map\nMean Monthly Temperatures, 1894-2013\n" "Saint Francis, KS, USA"), fontsize=20) sns.heatmap(temps, cmap=temps_cmap, cbar_kws={"label": "Temperature (F)"}) figure.tight_layout()
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
If you want to render your plot as the book has published it, you can do the following instead: ```python sns.set(font_scale=1.8) (figure, axes) = plt.subplots(figsize=(17,9)) axes.set_title(("Heat Map\nMean Monthly Temperatures, 1894-2013\n" "Saint Francis, KS, USA"), fontsize=24) xticks = temps.column...
clustermap = sns.clustermap( temps, figsize=(19, 12), cbar_kws={"label": "Temperature\n(F)"}, cmap=temps_cmap) _ = clustermap.ax_col_dendrogram.set_title( "Cluster Map\nMean Monthly Temperatures, 1894-2013\nSaint Francis, KS, USA", fontsize=20)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
For the book version: ```python sns.set(font_scale=1.5) xticks = temps.columns keptticks = xticks[::int(len(xticks)/36)] xticks = ['' for y in xticks] xticks[::int(len(xticks)/36)] = keptticks clustermap = sns.clustermap( temps, figsize=(19, 12), linewidth=0, xticklabels=xticks, cmap=temps_cmap,...
clustermap = sns.clustermap( temps, z_score=1, figsize=(19, 12), cbar_kws={"label": "Normalized\nTemperature (F)"}) _ = clustermap.ax_col_dendrogram.set_title( "Normalized Cluster Map\nMean Monthly Temperatures, 1894-2013\nSaint Francis, KS, USA", fontsize=20)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
For the book version: python sns.set(font_scale=1.5) clustermap = sns.clustermap( temps, z_score=1, figsize=(19, 12), linewidth=0, xticklabels=xticks, cbar_kws={"label": "Normalized\nTemperature (F)"}) _ = clustermap.ax_col_dendrogram.set_title( "Normalized Cluster Map\nMean Monthly Temperatures, 1894-...
figure = plt.figure(figsize=(18,13)) grid_spec = plt.GridSpec(2, 2, width_ratios=[50, 1], height_ratios=[1, 3], wspace=0.05, hspace=0.05) scatter_axes = figure.add_subplot(grid_spec[0]) cluster_axes = figure.add_subplot(grid_spec[2]) colorbar_ax...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
For the book version: ```python sns.set(font_scale=1.8) figure = plt.figure(figsize=(18,13)) grid_spec = plt.GridSpec(2, 2, width_ratios=[50, 1], height_ratios=[1, 3], wspace=0.05, hspace=0.05) scatter_axes = figure.add_subplot(grid_spec[0]) clu...
temps2 = data_raw.pivot("Year", "Month", "Mean Temperature (F)") temps2.columns = [str(x).zfill(2) + " - " + calendar.month_name[x] for x in temps2.columns] monthly_means = temps2.mean() temps2.head()
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Now we're ready for our histogram. We'll use the histogram provided by Pandas for this. Unfortunately, Pandas does not return the figure and axes that it creates with its hist wrapper. Instead, it returns an NumPy array of subplots. As such, we're left with fewer options than we might like for further tweaking of the p...
axes = temps2.hist(figsize=(16,12)) plt.text(-20, -10, "Temperatures (F)", fontsize=16) plt.text(-74, 77, "Counts", rotation="vertical", fontsize=16) _ = plt.suptitle("Temperatue Counts by Month, 1894-2013\nSaint Francis, KS, USA", fontsize=20)
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
This provides a nice view on the number of occurrences for temperature ranges in each month over the course of the century. Now what we'd like to do is: * look at the mean temperature for all months over the century * but also show the constituent data that generated that mean * and trace the max, mean, and min temp...
from scipy.interpolate import UnivariateSpline smooth_mean = UnivariateSpline(month_nums, list(monthly_means), s=0.5) means_xs = np.linspace(0, 13, 2000) means_ys = smooth_mean(means_xs) smooth_maxs = UnivariateSpline(month_nums, list(temps2.max()), s=0) maxs_xs = np.linspace(0, 13, 2000) maxs_ys = smooth_maxs(maxs_x...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
We'll use the raw data from the beginning of this section, since we'll be doing interpolation on our $x$ values (month numbers):
temps3 = data_raw[["Month", "Mean Temperature (F)"]]
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Now we can plot our means for all months, a scatter plot (as lines, in this case) for each month superimposed over each mean, and finally our max/mean/min interpolations:
(figure, axes) = plt.subplots(figsize=(18,10)) axes.bar(month_nums, monthly_means, width=0.96, align="center", alpha=0.6) axes.scatter(temps3["Month"], temps3["Mean Temperature (F)"], s=2000, marker="_", alpha=0.6) axes.plot(means_xs, means_ys, "b", linewidth=6, alpha=0.6) axes.plot(maxs_xs, maxs_ys, "r", linewidth=6, ...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
When we created our by-month pivot (the assigned to the temps2 variable), we provided ourselves with the means to easily look at statistical data for each month. We'll print out the highlights below so we can look at the numbers in preparation for sanity checking our visuals on the next plot:
temps2.max() temps2.mean() temps2.min()
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
We've seen those above (in various forms). We haven't seen the standard deviation for this data yet, though:
temps2.std()
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Have a good look at those numbers; we're going to use them to make sure that our box plot results make sense in the next plot. What is a box plot? The box plot was invented by the famous statistical mathematician John Tukey (the inventor of many important concepts, he is often forgotten as the person who coined the ter...
(figure, axes) = plt.subplots(figsize=(18,10)) axes.bar(month_nums, monthly_means, width=0.96, align="center", alpha=0.6) axes.scatter(temps3["Month"], temps3["Mean Temperature (F)"], s=2000, marker="_", alpha=0.6) sns.boxplot(temps2, ax=axes) axes.axis((0.5, 12.5, temps_degrees.min() - 5, temps_degrees.max() + 5)) axe...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Now we can easily identify the spread, the outliers, the area that contains 50% of the distribution, etc. The violin plot, as previously mentioned, is a variation on the box plot, it's shape indicating the probability distribution of the data in that particular set. We will configure it to show our data points as lines...
sns.set(style="whitegrid") (figure, axes) = plt.subplots(figsize=(18, 10)) sns.violinplot(temps2, bw=0.2, lw=1, inner="stick") axes.set_title(("Violin Plots\nMean Monthly Temperatures, 1894-2013\n" "Saint Francis, KS, USA"), fontsize=20) axes.set_xticks(month_nums) axes.set_xticklabels(month_names) _ =...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
With the next plot, Andrews' curves, we reach the end of the section on temperature analysis. The application of Andrews' curves to this particular data set is a bit forced. It's a more useful analysis tool when applied to data sets with higher dimensionality, due to the fact that the computed curves can reveal structu...
months_cmap = sns.cubehelix_palette(8, start=-0.5, rot=0.75, as_cmap=True) (figure, axes) = plt.subplots(figsize=(18, 10)) temps4 = data_raw[["Mean Temperature (F)", "Month"]] axes.set_xticks([-np.pi, -np.pi/2, 0, np.pi/2, np.pi]) axes.set_xticklabels([r"$-{\pi}$", r"$-\frac{\pi}{2}$", r"$0$", r"$\frac{\pi}{2}$", r"${...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Andrews' curves are groups of lines where each line represents a point in the input data set. The line itself is a the plot of a finite Fourier series, as defined below (taken from the paper linked above). Each data point $x = \left { x_1, x_2, \ldots x_d \right }$ defines a finite Fourier series: \begin{align} f_x(t) ...
sns.set(style="darkgrid") precips_colors = ["#f2d98f", "#f8ed39", "#a7cf38", "#7fc242", "#4680c2", "#3a53a3", "#6e4a98"] sns.palplot(precips_colors) precips_cmap = mpl.colors.LinearSegmentedColormap.from_list("precip colors", precips_colors) (figure, axes) = plt.subplots(figsize=(17,9)) axes.set_title(("Heat Map\nMe...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
For the book version: ```python sns.set(font_scale=1.8) figure = plt.figure(figsize=(18, 13)) grid_spec = plt.GridSpec(2, 2, width_ratios=[50, 1], height_ratios=[1, 3], wspace=0.05, hspace=0.05) hist_axes = figure.add_subplot(grid_spec[0]) clust...
clustermap = sns.clustermap( precips, figsize=(19, 12), cbar_kws={"label": "Precipitation\n(F)"}, cmap=precips_cmap) _ = clustermap.ax_col_dendrogram.set_title( "Cluster Map\nMean Monthly Precipitation, 1894-2013\nSaint Francis, KS, USA", fontsize=20) clustermap = sns.clustermap( precips, z_sco...
github/MasteringMatplotlib/mmpl-high-level.ipynb
moonbury/pythonanywhere
gpl-3.0
Create an :class:info <mne.Info> object.
# It is also possible to use info from another raw object. info = mne.create_info(ch_names=ch_names, sfreq=sfreq, ch_types=ch_types)
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
Create a dummy :class:mne.io.RawArray object
raw = mne.io.RawArray(data, info) # Scaling of the figure. # For actual EEG/MEG data different scaling factors should be used. scalings = {'mag': 2, 'grad': 2} raw.plot(n_channels=4, scalings=scalings, title='Data from arrays', show=True, block=True) # It is also possible to auto-compute scalings scalings =...
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
EpochsArray
event_id = 1 # This is used to identify the events. # First column is for the sample number. events = np.array([[200, 0, event_id], [1200, 0, event_id], [2000, 0, event_id]]) # List of three arbitrary events # Here a data set of 700 ms epochs from 2 channels is # created from si...
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
EvokedArray
nave = len(epochs_data) # Number of averaged epochs evoked_data = np.mean(epochs_data, axis=0) evokeds = mne.EvokedArray(evoked_data, info=info, tmin=-0.2, comment='Arbitrary', nave=nave) evokeds.plot(picks=picks, show=True, units={'mag': '-'}, titles={'mag': 'sin and cos averag...
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
Create epochs by windowing the raw data.
# The events are spaced evenly every 1 second. duration = 1. # create a fixed size events array # start=0 and stop=None by default events = mne.make_fixed_length_events(raw, event_id, duration=duration) print(events) # for fixed size events no start time before and after event tmin = 0. tmax = 0.99 # inclusive tmax,...
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
Create overlapping epochs using :func:mne.make_fixed_length_events (50 % overlap). This also roughly doubles the amount of events compared to the previous event list.
duration = 0.5 events = mne.make_fixed_length_events(raw, event_id, duration=duration) print(events) epochs = mne.Epochs(raw, events=events, tmin=tmin, tmax=tmax, baseline=None, verbose=True) epochs.plot(scalings='auto', block=True)
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
Extracting data from NEO file
# The example here uses the ExampleIO object for creating fake data. # For actual data and different file formats, consult the NEO documentation. reader = neo.io.ExampleIO('fakedata.nof') bl = reader.read(lazy=False)[0] # Get data from first (and only) segment seg = bl.segments[0] title = seg.file_origin ch_names = l...
0.19/_downloads/04c2d1e64afcdd4e5032afb2212a74e5/plot_objects_from_arrays.ipynb
mne-tools/mne-tools.github.io
bsd-3-clause
Creating a ScaleBar object The only required parameter for creating a ScaleBar object is dx. This is equal to a size of one pixel in real world. Value of this parameter depends on units of your CRS. Projected coordinate system (meters) The easiest way to add a scale bar is using a projected coordinate system with meter...
nybb = gpd.read_file(gpd.datasets.get_path('nybb')) nybb = nybb.to_crs(32619) # Convert the dataset to a coordinate # system which uses meters ax = nybb.plot() ax.add_artist(ScaleBar(1))
doc/source/gallery/matplotlib_scalebar.ipynb
jorisvandenbossche/geopandas
bsd-3-clause
Geographic coordinate system (degrees) With a geographic coordinate system with degrees as units, dx should be equal to a distance in meters of two points with the same latitude (Y coordinate) which are one full degree of longitude (X) apart. You can calculate this distance by online calculator (e.g. the Great Circle c...
from shapely.geometry.point import Point points = gpd.GeoSeries([Point(-73.5, 40.5), Point(-74.5, 40.5)], crs=4326) # Geographic WGS 84 - degrees points = points.to_crs(32619) # Projected WGS 84 - meters
doc/source/gallery/matplotlib_scalebar.ipynb
jorisvandenbossche/geopandas
bsd-3-clause
After the conversion, we can calculate the distance between the points. The result slightly differs from the Great Circle Calculator but the difference is insignificant (84,921 and 84,767 meters):
distance_meters = points[0].distance(points[1])
doc/source/gallery/matplotlib_scalebar.ipynb
jorisvandenbossche/geopandas
bsd-3-clause
Finally, we are able to use geographic coordinate system in our plot. We set value of dx parameter to a distance we just calculated:
nybb = gpd.read_file(gpd.datasets.get_path('nybb')) nybb = nybb.to_crs(4326) # Using geographic WGS 84 ax = nybb.plot() ax.add_artist(ScaleBar(distance_meters))
doc/source/gallery/matplotlib_scalebar.ipynb
jorisvandenbossche/geopandas
bsd-3-clause
Using other units The default unit for dx is m (meter). You can change this unit by the units and dimension parameters. There is a list of some possible units for various values of dimension below: | dimension | units | | ----- |:-----:| | si-length | km, m, cm, um| | imperial-length |in, ft, yd, mi| |si-length-rec...
nybb = gpd.read_file(gpd.datasets.get_path('nybb')) ax = nybb.plot() ax.add_artist(ScaleBar(1, dimension="imperial-length", units="ft"))
doc/source/gallery/matplotlib_scalebar.ipynb
jorisvandenbossche/geopandas
bsd-3-clause
Customization of the scale bar
nybb = gpd.read_file(gpd.datasets.get_path('nybb')).to_crs(32619) ax = nybb.plot() # Position and layout scale1 = ScaleBar( dx=1, label='Scale 1', location='upper left', # in relation to the whole plot label_loc='left', scale_loc='bottom' # in relation to the line ) # Color scale2 = ScaleBar( dx=1, labe...
doc/source/gallery/matplotlib_scalebar.ipynb
jorisvandenbossche/geopandas
bsd-3-clause
Model specification Here we set some specifications for the model: type, how it should be fitted, optimized and validated.
model_type = 'rf' # the classification algorithm tune_model = False # optimize hyperparameters cross_val_method = 'temporal' # cross-validation routine cost_fp = 1000 # preferably in euros! benefit_tp = 3000 class_weights = {0: cost_fp, 1: benefit_tp} # costs for fn and fp
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Cross-validation procedure To validate whether the model makes sensible predictions, we need to perform cross-validation. The exact procedure for this is specified below. Random cross-validation (set-aside a random sample for testing) is fast, but temporal cross-validation (set-aside a time period for testing) gives th...
from sklearn.model_selection import StratifiedShuffleSplit, GridSearchCV, train_test_split #source: https://github.com/BigDataRepublic/bdr-analytics-py #! pip install -e git+ssh://git@github.com/BigDataRepublic/bdr-analytics.git#egg=bdranalytics-0.1 from bdranalytics.pipeline.encoders import WeightOfEvidenceEncoder fr...
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Model parameter tuning If desired, we can optimize the model hyperparameters to get the best possible model.
# procedure depends on cross-validation type if cross_val_method is 'random': train_index = next(cv_test.split(X, y))[0] X_dev = X.iloc[train_index,:] y_dev = y[train_index] elif cross_val_method is 'temporal': X_dev = X y_dev = y # setting to include class weights in the gradient boosting model i...
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Model validation The final test on the holdout.
y_pred_proba = [] # initialize empty predictions array y_true = [] # initialize empty ground-truth array # loop over the test folds for i_fold, (train_index, test_index) in enumerate(cv_test.split(X, y)): print "validation fold {:d}".format(i_fold) X_train = X.iloc[train_index,:] y_train = y[tr...
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Receiver-operator characteristics Line is constructed by applying various threshold to the model output. Y-axis: proportion of events correctly identified, hit-rate X-axis: proportion of false positives, usually results in waste of resources Dotted line is guessing (no model). Blue line above the dotted line means th...
from sklearn.metrics import roc_curve, auc fpr, tpr, thresholds = roc_curve(y_true, y_pred_proba, pos_label=1) roc_auc = auc(fpr, tpr) # plot ROC curve plt.figure() plt.plot(fpr, tpr, label="ROC curve (area = {:.2f})".format(roc_auc)) plt.plot([0, 1], [0, 1], 'k--') plt.xlim([0.0, 1.0]) plt.ylim([0.0, 1.0]) plt....
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Costs and benefits ROC optimization with cost matrix. Critical information: cost of FP and cost of FN (i.e. benefit of TP). Also used to train the model with class_weights.
def benefit(tpr, fpr): n_tp = tpr * n_pos_test # number of true positives (benefits) n_fp = fpr * n_neg_test # number of false positives (extra costs) fp_costs = n_fp * cost_fp tp_benefits = n_tp * benefit_tp return tp_benefits - fp_costs benefits = np.zeros_like(thresholds) for i, _ ...
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Precision-recall curve Another way to look at it. Note that models which perform well in PR-space are necessarily also dominating ROC-space. The opposite is not the case! Line is constructed by applying various threshold to the model output. Y-axis: proportion of events among all positives (precision) X-axis: proportio...
from sklearn.metrics import precision_recall_curve precision, recall, thresholds = precision_recall_curve(y_true, y_pred_proba, pos_label=1) average_precision = average_precision_score(y_true, y_pred_proba, average="micro") baseline = n_pos_test / n_samples_test # plot PR curve plt.figure() plt.plot(recall, precisi...
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Classification report
from sklearn.metrics import classification_report target_names = ['no event','event'] print classification_report(y_true, y_pred_bin, target_names=target_names, digits=3)
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Confusion matrix
from sklearn.metrics import confusion_matrix confusion = pd.DataFrame(confusion_matrix(y_true, y_pred_bin), index=target_names, columns=target_names) sns.heatmap(confusion, annot=True, fmt="d") plt.xlabel('predicted label') plt.ylabel('true label')
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Accuracies at different classifier thresholds
from sklearn.metrics import accuracy_score thresholds = (np.arange(0,100,1) / 100.) acc = map(lambda thresh: accuracy_score(y_true, map(lambda prob: prob > thresh, y_pred_proba)), thresholds) plt.hist(acc, bins=20);
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Thresholds versus accuracy
plt.plot(thresholds, acc);
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
Feature importance Note that these models are optimized to make accurate predictions, and not to make solid statistical inferences.
feature_labels = filter(lambda k: y_col not in k, df.columns.values) if model_type is 'lr': weights = estimator._final_estimator.coef_[0] elif model_type in ['rf','gbc']: weights = estimator._final_estimator.feature_importances_ elif model_type is 'dummy': print 'DummyClassifier does not have weights' ...
notebooks/bdr-imbalanced-classification.ipynb
BigDataRepublic/bdr-analytics-py
apache-2.0
As an example, consider the following multilayer perceptron with one hidden layer and a softmax output layer.
ninputs = 1000 nfeatures = 100 noutputs = 10 nhiddens = 50 rng = np.random.RandomState(0) x = T.dmatrix('x') wh = th.shared(rng.normal(0, 1, (nfeatures, nhiddens)), borrow=True) bh = th.shared(np.zeros(nhiddens), borrow=True) h = T.nnet.sigmoid(T.dot(x, wh) + bh) wy = th.shared(rng.normal(0, 1, (nhiddens, noutputs)))...
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
The function predict outputs the probability of 10 classes. You can visualize it with pydotprint as follows:
from theano.printing import pydotprint import os if not os.path.exists('examples'): os.makedirs('examples') pydotprint(predict, 'examples/mlp.png') from IPython.display import Image Image('examples/mlp.png', width='80%')
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
To visualize it interactively, import the d3viz function from the d3viz module, which can be called as before:
import theano.d3viz as d3v d3v.d3viz(predict, 'examples/mlp.html')
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
Open visualization! When you open the output file mlp.html in your web-browser, you will see an interactive visualization of the compute graph. You can move the whole graph or single nodes via drag and drop, and zoom via the mouse wheel. When you move the mouse cursor over a node, a window will pop up that displays det...
predict_profiled = th.function([x], y, profile=True) x_val = rng.normal(0, 1, (ninputs, nfeatures)) y_val = predict_profiled(x_val) d3v.d3viz(predict_profiled, 'examples/mlp2.html')
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
Open visualization! When you open the HTML file in your browser, you will find an additional Toggle profile colors button in the menu bar. By clicking on it, nodes will be colored by their compute time, where red corresponds to a high compute time. You can read out the exact timing information of a node by moving the c...
formatter = d3v.formatting.PyDotFormatter() pydot_graph = formatter(predict_profiled) pydot_graph.write_png('examples/mlp2.png'); pydot_graph.write_pdf('examples/mlp2.pdf'); Image('./examples/mlp2.png')
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
Here, we used the PyDotFormatter class to convert the compute graph into a pydot graph, and created a PNG and PDF file. You can find all output formats supported by Graphviz here. OpFromGraph nodes An OpFromGraph node defines a new operation, which can be called with different inputs at different places in the compute ...
x, y, z = T.scalars('xyz') e = T.nnet.sigmoid((x + y + z)**2) op = th.OpFromGraph([x, y, z], [e]) e2 = op(x, y, z) + op(z, y, x) f = th.function([x, y, z], e2) d3v.d3viz(f, 'examples/ofg.html')
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
Open visualization! In this example, an operation with three inputs is defined, which is used to build a function that calls this operations twice, each time with different input arguments. In the d3viz visualization, you will find two OpFromGraph nodes, which correspond to the two OpFromGraph calls. When you double c...
x, y, z = T.scalars('xyz') e = x * y op = th.OpFromGraph([x, y], [e]) e2 = op(x, y) + z op2 = th.OpFromGraph([x, y, z], [e2]) e3 = op2(x, y, z) + z f = th.function([x, y, z], [e3]) d3v.d3viz(f, 'examples/ofg2.html')
libs/Theano/doc/library/d3viz/index.ipynb
rizar/attention-lvcsr
mit
Helper Functions Determine data types
def get_type_lists(frame, rejects=['Id', 'SalePrice']): """Creates lists of numeric and categorical variables. :param frame: The frame from which to determine types. :param rejects: Variable names not to be included in returned lists. :return: Tuple of lists for numeric and categorical variables i...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Impute with GLRM
def glrm_num_impute(role, frame): """ Helper function for imputing numeric variables using GLRM. :param role: Role of frame to be imputed. :param frame: H2OFrame to be imputed. :return: H2OFrame of imputed numeric features. """ # count missing values in training data numeric colu...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Embed with GLRM
def glrm_cat_embed(frame): """ Helper function for embedding caetgorical variables using GLRM. :param frame: H2OFrame to be embedded. :return: H2OFrame of embedded categorical features. """ # initialize GLRM cat_embed_glrm = H2OGeneralizedLowRankEstimator( k=50, ...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Import data
train = h2o.import_file('../../03_regression/data/train.csv') test = h2o.import_file('../../03_regression/data/test.csv') # bug fix - from Keston dummy_col = np.random.rand(test.shape[0]) test = test.cbind(h2o.H2OFrame(dummy_col)) cols = test.columns cols[-1] = 'SalePrice' test.columns = cols print(train.shape) print(...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Split into to train and validation (before doing data prep!!!)
train, valid = train.split_frame([0.7], seed=12345) print(train.shape) print(valid.shape)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Impute numeric missing using GLRM matrix completion Training data
train_num_impute = glrm_num_impute('training', train) train_num_impute.head()
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Validation data
valid_num_impute = glrm_num_impute('validation', valid)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Test data
test_num_impute = glrm_num_impute('test', test)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Embed categorical vars using GLRM Training data
train_cat_embed = glrm_cat_embed(train)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Validation data
valid_cat_embed = glrm_cat_embed(valid)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Test data
test_cat_embed = glrm_cat_embed(test)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Merge imputed and embedded frames
imputed_embedded_train = train[['Id', 'SalePrice']].cbind(train_num_impute).cbind(train_cat_embed) imputed_embedded_valid = valid[['Id', 'SalePrice']].cbind(valid_num_impute).cbind(valid_cat_embed) imputed_embedded_test = test[['Id', 'SalePrice']].cbind(test_num_impute).cbind(test_cat_embed)
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Redefine numerics and explore
imputed_embedded_nums, cats = get_type_lists(imputed_embedded_train) print('Imputed and encoded numeric training data:') imputed_embedded_train.describe() print('--------------------------------------------------------------------------------') print('Imputed and encoded numeric validation data:') imputed_embedded_va...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Train model on imputed, embedded features
h2o.show_progress() # turn on progress bars # Check log transform - looks good %matplotlib inline imputed_embedded_train['SalePrice'].log().as_data_frame().hist() # Execute log transform imputed_embedded_train['SalePrice'] = imputed_embedded_train['SalePrice'].log() imputed_embedded_valid['SalePrice'] = imputed_embed...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
Train GLM on imputed, embedded inputs
alpha_opts = [0.01, 0.25, 0.5, 0.99] # always keep some L2 hyper_parameters = {"alpha":alpha_opts} # initialize grid search grid = H2OGridSearch( H2OGeneralizedLinearEstimator( family="gaussian", lambda_search=True, seed=12345), hyper_params=hyper_parameters) # train grid grid.trai...
09_matrix_factorization/src/py_part_9_kaggle_GLRM_example.ipynb
jphall663/GWU_data_mining
apache-2.0
The second line of this code uses the keyword if to tell Python that we want to make a choice. If the test that follows the if statement is true, the body of the if (i.e., the set of lines indented underneath it) is executed, and “greater” is printed. If the test is false, the body of the else is executed instead, and ...
num = -3 if num > 0: print(num, 'is positive') elif num == 0: print(num, 'is zero') else: print(num, 'is negative')
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
Note that to test for equality we use a double equals sign == rather than a single equals sign = which is used to assign values. Along with the > and == operators we have already used for comparing values in our conditionals, there are a few more options to know about: >: greater than <: less than ==: equal to !...
if (1 > 0) and (-1 >= 0): print('both parts are true') else: print('at least one part is false')
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
while or is true if at least one part is true:
if (1 < 0) or (1 >= 0): print('at least one test is true')
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
Activity 3: Checking our Data Now that we’ve seen how conditionals work, we can use them to check for the suspicious features we saw in our inflammation data. We are about to use functions provided by the numpy module again.
import numpy as np data = np.loadtxt("./swc-python/data/inflammation-01.csv", delimiter=",")
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
From the first couple of plots, we saw that maximum daily inflammation exhibits a strange behavior and raises one unit a day. Wouldn’t it be a good idea to detect such behavior and report it as suspicious? Let’s do that! However, instead of checking every single day of the study, let’s merely check if maximum inflammat...
max_inflammation_0 = np.max(data, axis=0)[0] max_inflammation_20 = np.max(data, axis=0)[20] if max_inflammation_0 == 0 and max_inflammation_20 == 20: print('Suspicious looking maxima!')
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
We also saw a different problem in the third dataset; the minima per day were all zero (looks like a healthy person snuck into our study). We can also check for this with an elif condition:
if max_inflammation_0 == 0 and max_inflammation_20 == 20: print('Suspicious looking maxima!') elif np.sum(np.min(data, axis=0)) == 0: print('Minima add up to zero!')
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
And if neither of these conditions are true, we can use else to give the all-clear:
if max_inflammation_0 == 0 and max_inflammation_20 == 20: print('Suspicious looking maxima!') elif np.sum(np.min(data, axis=0)) == 0: print('Minima add up to zero!') else: print('Seems OK!')
teaching/stat_775_2021_fall/activities/activity-2021-09-15.ipynb
cgrudz/cgrudz.github.io
mit
Tests (1/2)
s = '1001111011000010' lempel_ziv_complexity(s) # 1 / 0 / 01 / 11 / 10 / 110 / 00 / 010 %timeit lempel_ziv_complexity(s) lempel_ziv_complexity('1010101010101010') # 1, 0, 10, 101, 01, 010, 1010 lempel_ziv_complexity('1001111011000010000010') # 1, 0, 01, 11, 10, 110, 00, 010, 000 lempel_ziv_complexity('1001111011...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
We can start to see that the time complexity of this function seems to grow linearly as the size grows. Cython implementation As this blog post explains it, we can easily try to use Cython in a notebook cell. See the Cython documentation for more information.
%load_ext cython %%cython import cython ctypedef unsigned int DTYPE_t @cython.boundscheck(False) # turn off bounds-checking for entire function, quicker but less safe def lempel_ziv_complexity_cython(str sequence not None): """Lempel-Ziv complexity for a string, in simple Cython code (C extension).""" c...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
Let try it!
s = '1001111011000010' lempel_ziv_complexity_cython(s) # 1 / 0 / 01 / 11 / 10 / 110 / 00 / 010 %timeit lempel_ziv_complexity(s) %timeit lempel_ziv_complexity_cython(s) lempel_ziv_complexity_cython('1010101010101010') # 1, 0, 10, 101, 01, 010, 1010 lempel_ziv_complexity_cython('1001111011000010000010') # 1, 0, 01,...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
Now for a test of the speed?
for (r, name) in zip( [random_string, random_binary_sequence], ["random strings in A..Z", "random binary sequences"] ): print("\nFor {}...".format(name)) for n in [10, 100, 1000, 10000, 100000]: print(" of sizes {}, Lempel-Ziv complexity in Cython runs in:".format(n)) %timeit lempel...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
$\implies$ Yay! It seems faster indeed! but only x2 times faster... Numba implementation As this blog post explains it, we can also try to use Numba in a notebook cell.
from numba import jit @jit def lempel_ziv_complexity_numba(sequence : str) -> int: """Lempel-Ziv complexity for a sequence, in Python code using numba.jit() for automatic speedup (hopefully).""" sub_strings = set() n : int= len(sequence) ind : int = 0 inc : int = 1 while True: if ind ...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
Let try it!
s = '1001111011000010' lempel_ziv_complexity_numba(s) # 1 / 0 / 01 / 1110 / 1100 / 0010 %timeit lempel_ziv_complexity_numba(s) lempel_ziv_complexity_numba('1010101010101010') # 1, 0, 10, 101, 01, 010, 1010 lempel_ziv_complexity_numba('1001111011000010000010') # 1, 0, 01, 11, 10, 110, 00, 010, 000 9 lempel_zi...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
$\implies$ Well... It doesn't seem that much faster from the naive Python code. We specified the signature when calling @numba.jit, and used the more appropriate data structure (string is probably the smaller, numpy array are probably faster). But even these tricks didn't help that much. I tested, and without specifyin...
from numpy.random import binomial def bernoulli(p, size=1): """One or more samples from a Bernoulli of probability p.""" return binomial(1, p, size) bernoulli(0.5, 20)
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
That's probably not optimal, but we can generate a string with:
''.join(str(i) for i in bernoulli(0.5, 20)) def random_binary_sequence(n, p=0.5): """Uniform random binary sequence of size n, with rate of 0/1 being p.""" return ''.join(str(i) for i in bernoulli(p, n)) random_binary_sequence(50) random_binary_sequence(50, p=0.1) random_binary_sequence(50, p=0.25) random_bin...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
And so, this function can test to check that the three implementations (naive, Cython-powered, Numba-powered) always give the same result.
def tests_3_functions(n, p=0.5, debug=True): s = random_binary_sequence(n, p=p) c1 = lempel_ziv_complexity(s) if debug: print("Sequence s = {} ==> complexity C = {}".format(s, c1)) c2 = lempel_ziv_complexity_cython(s) c3 = lempel_ziv_complexity_numba(s) assert c1 == c2 == c3, "Error: the...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
Benchmarks On two example of strings (binary sequences), we can compare our three implementation.
%timeit lempel_ziv_complexity('100111101100001000001010') %timeit lempel_ziv_complexity_cython('100111101100001000001010') %timeit lempel_ziv_complexity_numba('100111101100001000001010') %timeit lempel_ziv_complexity('10011110110000100000101000100100101010010111111011001111111110101001010110101010') %timeit lempel_ziv...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit
Let check the time used by all the three functions, for longer and longer sequences:
%timeit tests_3_functions(10, debug=False) %timeit tests_3_functions(20, debug=False) %timeit tests_3_functions(40, debug=False) %timeit tests_3_functions(80, debug=False) %timeit tests_3_functions(160, debug=False) %timeit tests_3_functions(320, debug=False) def test_cython(n): s = random_binary_sequence(n) c...
Short_study_of_the_Lempel-Ziv_complexity.ipynb
Naereen/Lempel-Ziv_Complexity
mit