Matplotlib axis label: heta does not work \Theta does

Question

I have a weird behaviour in matplotlib. Using the following I get a nice and shiny big theta. As soon as I use `	heta` instead of `\Theta` I get heta as an axis label ``` plt.figure(**pd.figpropsHP) line=pd.lineCycler() for i in range(2): for j in range(length-1): velocity[i,j]=(velocity[i,j+1]-velocity[i,j])*1000 #multiplied with sampling rate plt.plot(velocity[i,startstop[0]:startstop[1]],**next(line)) #plt.show(pPosition) plt.xlabel("t[ms]") plt.ylabel("$\dot{\Theta}$[deg/s]") plt.ylim(-3000,-3000+yrangeV) plt.annotate('30ms',fontsize='9', xy=(30, -1000),xytext=(40, -1000),verticalalignment='center',arrowprops=myarrow) plt.annotate('8ms',fontsize='9', xy=(8, -1700),xytext=(40, -1700),verticalalignment='center',arrowprops=myarrow) plt.axvline(x=span2Stop,lw='0.3',c='0.5') plt.axvspan(spanStart, spanStop, facecolor='0.9', alpha=1,edgecolor='0.9',lw=0) plt.tight_layout() plt.savefig(imagePath + "collisionTestbedVmot.pdf") ``` Any ideas what I am doing wrong? I sadly do not have any t…

Accepted Answer

If you specify that the string is raw text (a `r` before the quotation mark), it works. Like this:

```
plt.ylabel(r"$\dot{\Theta}$[deg/s]")
```

The reason you got an unexpected result is that `	` means a tab. So if you type `	heta`, it is parsed as `	` and following `heta`. If you specify it a a raw string, backslashes and python escapes will not be treated.

If you don't use raw strings, you have to escape the backslash (`\`) so python treats it as a backslash and not as a tab symbol (so as 	heta and not as 	 and heta). That's why `\theta` did the job. To avoid always have to write double backslashes, use raw strings when using latex, since it uses backslashes a lot for special characters.

Matplotlib axis label: \theta does not work \Theta does

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