# removing leading 0 from matplotlib tick label formatting

How can I change the ticklabels of numeric decimal data (say between 0 and 1) to be "0", ".1", ".2" rather than "0.0", "0.1", "0.2" in matplotlib? For example,

hist(rand(100)) xticks([0, .2, .4, .6, .8])

will format the labels as "0.0", "0.2", etc. I know that this gets rid of the leading "0" from "0.0" and the trailing "0" on "1.0":

from matplotlib.ticker import FormatStrFormatter majorFormatter = FormatStrFormatter('%g') myaxis.xaxis.set_major_formatter(majorFormatter)

That's a good start, but I also want to get rid of the "0" prefix on "0.2" and "0.4", etc. How can this be done?

## Answers

Although I am not sure it is the best way, you can use a matplotlib.ticker.FuncFormatter to do this. For example, define the following function.

def my_formatter(x, pos): """Format 1 as 1, 0 as 0, and all values whose absolute values is between 0 and 1 without the leading "0." (e.g., 0.7 is formatted as .7 and -0.4 is formatted as -.4).""" val_str = '{:g}'.format(x) if np.abs(x) > 0 and np.abs(x) < 1: return val_str.replace("0", "", 1) else: return val_str

Now, you can use majorFormatter = FuncFormatter(my_formatter) to replace the majorFormatter in the question.

##### Complete example

Let's look at a complete example.

from matplotlib import pyplot as plt from matplotlib.ticker import FuncFormatter import numpy as np def my_formatter(x, pos): """Format 1 as 1, 0 as 0, and all values whose absolute values is between 0 and 1 without the leading "0." (e.g., 0.7 is formatted as .7 and -0.4 is formatted as -.4).""" val_str = '{:g}'.format(x) if np.abs(x) > 0 and np.abs(x) < 1: return val_str.replace("0", "", 1) else: return val_str # Generate some data. np.random.seed(1) # So you can reproduce these results. vals = np.random.rand((1000)) # Set up the formatter. major_formatter = FuncFormatter(my_formatter) plt.hist(vals, bins=100) ax = plt.subplot(111) ax.xaxis.set_major_formatter(major_formatter) plt.show()

Running this code generates the following histogram.

Notice the tick labels satisfy the conditions requested in the question.

Multiple all your values by 10?