avoid sorting in X axis in matplotlib and plot common X axis with multiple y axis

Question

I wish to clarify two queries in this post.

I have a pandas df like below picture.

1. Plotting problem : . When i try to plot column 0 with column 1, the values gets sorted.

example : in col_0 I have values starting from 112 till 0. the values gets sorted in ascending order and the graph shows reversed X axis plot when i use the below code.

plt.plot(df.col_0, df.col_1)

What will be best way to avoid sorting X axis values. ?

2. All paramaters in single graph I would like to plot all the params in a single plot. Except X axis all other params values are between 0 to 1 (same scale) What will be best pythonic way of doing. Any help would be appreciated.

Answer 1

Try to draw the series/dataframe against the index:

col_to_draw = [col for col in df.columns if col!='col0']

# if your data frame is indexed as 0,1,2,... ignore this step
tmp_df = df.reset_index()

ax = tmp_df[col_to_draw].plot(figsize=(10,6))
xtick_vals = ax.get_xticks()
ax.set_xticklabels(tmp_df.col0[xtick_vals].tolist())

Output:

Answer 2

I don't understand what you mean by they get sorted - does it not plot 112, 0.90178 and connect it to 110.89899, 0.90779, etc?

To share the X axis but have 2 Y axes that certain sets are plotted on, use twinx

fig, ax1 = plt.subplots()
ax1.plot(df.col_0, df.col_1)
ax2 = ax1.twinx()
ax2.plot(df.col_0, df.col_2)

re: how to plot in the order you want

I believe your intention is to actually plot these values vs. time or index. To that end, I suggest:

fig, ax1 = plt.subplots()
ax1.plot(df['Time'], df.col_0) # or df.index, df.col_0
ax2 = ax1.twinx()
ax2.plot(df['Time'], df.col_1)