Stream: helpdesk (published)

Topic: ✔ won't plot x values for histogram


view this post on Zulip Yuu Yin (Mar 26 2023 at 17:01):

I have

using Plots

classIntervals = range(start=1, step=2, stop=20)
frequencyAbsolute::AbstractVector = [1; 1; 11; 21; 25; 17; 9; 4; 1]
frequencyAbsoluteCumulative = sum(frequencyAbsolute)
frequencyRelative::AbstractVector = (frequencyAbsolute ./ frequencyAbsoluteCumulative)

histogram(x=frequencyRelative, bins=classIntervals, label="Experimental", color=:gray, normalize=:pdf)
xlims!(1, 19)
ylims!(0, 30)
xlabel!("x")
plotHistogram = ylabel!("P(x)")

savefig(plotHistogram, "out/plot-histogram.svg")

what is wrong with it that the x bars won't show up? i adapted example from https://docs.juliaplots.org/latest/series_types/histogram/

view this post on Zulip Daniel González (Mar 26 2023 at 17:12):

Not an expert on Plots, but it seems to me that the histogram function expects as x the actual values of the samples, not the binned counts (it will do that automatically, I guess). Since you're giving it a vector that is less than 1, it won't show up in bins that start at 1.

view this post on Zulip Daniel González (Mar 26 2023 at 17:15):

By the way, I believe annotating the vector as AbstractVector does not do anything beyond erroring out if the right hand side of the assignment is not a subtype of AbstractVector

view this post on Zulip Yuu Yin (Mar 26 2023 at 18:27):

@Daniel González thanks for the reply!

expects as x the actual values of the samples, not the binned counts (it will do that automatically, I guess).

do you mean the data set variable values, instead of any pre-processed frequency, right?

so i tried this

using Plots

x::AbstractVector = [
    02.97; 04.00; 05.20; 05.56; 05.94; 05.98; 06.35; 06.62; 06.72; 06.78;
    06.80; 06.85; 06.94; 07.15; 07.16; 07.23; 07.29; 07.62; 07.62; 07.69;
    07.73; 07.87; 07.93; 08.00; 08.26; 08.29; 08.37; 08.47; 08.54; 08.58;
    08.61; 08.67; 08.69; 08.81; 09.07; 09.27; 09.37; 09.43; 09.52; 09.58;
    09.60; 09.76; 09.82; 09.83; 09.83; 09.84; 09.96; 10.04; 10.21; 10.28;
    10.28; 10.30; 10.35; 10.36; 10.40; 10.49; 10.50; 10.64; 10.95; 11.09;
    11.12; 11.21; 11.29; 11.43; 11.62; 11.70; 11.70; 12.16; 12.19; 12.28;
    12.31; 12.62; 12.69; 12.71; 12.91; 12.92; 13.11; 13.38; 13.42; 13.43;
    13.47; 13.60; 13.96; 14.24; 14.35; 15.12; 15.24; 16.06; 16.90; 18.26;
]
classIntervals = range(start=1, step=2, length=19)

histogram(x=x, bins=classIntervals, label="Experimental", color=:gray, normalize=:pdf)
xlims!(1, 19)
ylims!(0, 30)
xlabel!("x")
plotHistogram = ylabel!("P(x)")

savefig(plotHistogram, "out/plot-histogram.svg")

but i have same issue

Since you're giving it a vector that is less than 1

what do you mean by that?

view this post on Zulip Daniel González (Mar 26 2023 at 18:32):

That works for me, but ylims! squeezes the plot (since the maximum frequency is <0.15). Regarding my previous comment, I meant that all the entries of the relative frequency vector are smaller than 1.0; therefore, since they are interpreted as samples, do not enter into any bin (the first bin is from 1 to 3 in your example)

view this post on Zulip Daniel González (Mar 26 2023 at 18:36):

Oh, I think for some reason it works if you do

histogram(x, bins=classIntervals, label="Experimental", color=:gray, normalize=:pdf)

but not if you do

histogram(x=x, bins=classIntervals, label="Experimental", color=:gray, normalize=:pdf)

view this post on Zulip Daniel González (Mar 26 2023 at 18:41):

Looking at the examples and documentation, it seems that histogram takes the data as the first positional argument, not as a keyword argument x.

view this post on Zulip Yuu Yin (Mar 26 2023 at 19:11):

@Daniel González

Following your suggestions, I

using Plots

# Define data
x::AbstractVector = [
    02.97; 04.00; 05.20; 05.56; 05.94; 05.98; 06.35; 06.62; 06.72; 06.78;
    06.80; 06.85; 06.94; 07.15; 07.16; 07.23; 07.29; 07.62; 07.62; 07.69;
    07.73; 07.87; 07.93; 08.00; 08.26; 08.29; 08.37; 08.47; 08.54; 08.58;
    08.61; 08.67; 08.69; 08.81; 09.07; 09.27; 09.37; 09.43; 09.52; 09.58;
    09.60; 09.76; 09.82; 09.83; 09.83; 09.84; 09.96; 10.04; 10.21; 10.28;
    10.28; 10.30; 10.35; 10.36; 10.40; 10.49; 10.50; 10.64; 10.95; 11.09;
    11.12; 11.21; 11.29; 11.43; 11.62; 11.70; 11.70; 12.16; 12.19; 12.28;
    12.31; 12.62; 12.69; 12.71; 12.91; 12.92; 13.11; 13.38; 13.42; 13.43;
    13.47; 13.60; 13.96; 14.24; 14.35; 15.12; 15.24; 16.06; 16.90; 18.26;
]
classIntervals = range(start=1, step=2, stop=19)

# Set and export plot
plotHistogram = histogram(x, bins=classIntervals, label="Experimental", color=:cool)
xlims!(0, 19)
ylims!(0, 30)
title!("energy consuption")
xlabel!("x")
ylabel!("Percent(x)")
savefig(plotHistogram, "out/plot-histogram.svg")

it works now. Thank you very much!

The only issue left is the exported image height and width which seems to cut the xlabel and ylabel. lookin at savefig help, it does not show any config for that.

view this post on Zulip Notification Bot (Mar 26 2023 at 19:44):

Yuu Yin has marked this topic as resolved.

view this post on Zulip Daniel González (Mar 26 2023 at 19:53):

Weird; when I run the code, the SVG has the labels as well!

view this post on Zulip Leandro Martínez (Mar 28 2023 at 20:24):

As a side note, you don´t need any of those ::AbstractVector annotations , and usually in Julia we separate values with commas (although what you did is not incorrect, just not common).


Last updated: Dec 28 2024 at 04:38 UTC