6.2.3 Slicing strings

Segments of strings can be cut out by using square brackets to slice the string:

pyxplot> poem = "On the last sabbath day of 1879$\backslash $n"
pyxplot> poem+= "Which shall be remembered for a very long time."
pyxplot> print poem[10]
t
pyxplot> print poem[10:]
t sabbath day of 1879$\backslash $nWhich shall be remembered for a very long time.
pyxplot> print poem[:10]
On the las
pyxplot> print poem[5:10]
e las
pyxplot> print poem[-10:]
long time.

If a single number is placed in the square brackets, a single character is taken out of the string. If two colon-separated numbers are specified, [x:y], then the substring from character position x up to but not including y is returned. If either x or y are omitted, then the start or end of the string is used respectively. If either number of negative, then it counts from the end of the string, $-1$ being the last character in the string.