How do I inspect one specific object in IPython

Question

I'm coming from MATLAB and am used to the `whos` command to get variable information such as shape and data type and often used this with a specific names (e.g., `whos Var1`). I know I can use `whos` in IPython as well; however, when I have a ton of variables and objects I'd like to be able to inspect one at a time and the MATLAB syntax fails. ``` a = [1,2,3] whos a No variables match your requested type. ``` I'm using the IPython shell within the Enthought Canopy IDE. Is there a command for this? Thanks, Aaron

Accepted Answer

The command `whos` and linemagic `%whos` are available in IPython, but are not part of standard Python. Both of these will list current variables, along with some information about them. You can specify a `type` to filter by, e.g.

```
whos
Variable   Type    Data/Info
----------------------------
a          list    n=3
b          int     2
c          str     hello

whos list
Variable   Type    Data/Info
----------------------------
a          list    n=3
```

The related command `who` or linemagic `%who` will produce a short list, showing the variable names only:

```
who
a

who list
a    
```

To inspect a specific variable the `?` is what you are looking for:

```
a?

Type:        list
String form: [1, 2, 3]
Length:      3
Docstring:
list() -> new empty list
list(iterable) -> new list initialized from iterable's items
```

If you want even more information about an object, such as a function. You can use two `?` in the form `word??` to get the complete object help. For example, to get the complete documentation for the type `int` you would use:

```
int??
Type:        type
String form: <type 'int'>
Namespace:   Python builtin
Docstring:
int(x=0) -> int or long
int(x, base=10) -> int or long

Convert a number or string to an integer, or return 0 if no arguments
are given.  If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead.

If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base.  The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4
```

How do I inspect one specific object in IPython

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