I have time series per minute that look as shown below. The format is like '"hh:mm"' as seen below

'"8:59"' '"9:00"' '"9:01"' '"9:02"' '"9:03"' '"9:04"' '"9:05"' '"9:06"' '"9:07"'

Is it possible to change these to hhmm format in matlab like 859 900 901 902 t0 a double format.

Answer:

You can use a function like `strrep`

or `regexprep`

to get rid of the colon in the string. For example:

```
t = {'"8:59"', '"9:00"', '"9:01"', '"9:02"'};
newt = strrep(t, ':', '');
newt = strrep(newt, '"', '');
newt = strrep(newt, ''', '');
```

Or the slightly bizarre `regexprep`

call:

```
newt = regexprep(t, '[''''"'':]', '');
```

Returns

```
newt =
'859' '900' '901' '902'
```

Which you can then use with `str2double`

to generate your vector of doubles:

```
tdouble = str2double(newt);
```

Which returns:

```
tdouble =
859 900 901 902
```

I'd also recommend taking a look at `datenum`

and `datestr`

, which are the MATLAB builtins for manipulating serial date values. For example:

```
tother = datenum(t, 'HH:MM');
```

Returns:

```
tother =
1.0e+05 *
7.3597
7.3597
7.3597
7.3597
```

And to go back:

```
totherstr = datestr(tother, 'HH:MM');
```

Which returns:

```
totherstr =
08:59
09:00
09:01
09:02
```

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