# save

save workspace variables to .nh5 or .mat file

## 📝 Syntax

* save(filename)
* save(filename, version, var1, ..., varN)
* save(filename, '-append', ...)
* save(filename, '-mat', ...)
* save(filename, '-nh5', ...)
* save(filename, '-nocompression', ...)

## 📥 Input argument

* filename - a string: .nh5 or .mat filename. extension defines format used .mat or .nh5 (default)
* var1, ..., varN - string: Names of variables to save from Nelson's workspace.
* version: '-v7.3', '-v7', '-v6', '-v4' - mat file version used ('-v7.3'). This option will force '-mat'.
* '-mat' - forces to save as mat file (default '-nh5').
* '-nh5' - forces to save as nh5 file (default '-nh5').
* '-append' - append variables to an existing .nh5/.mat file (-v7.3 only).
* '-nocompression' - disable .nh5/.mat file compression.

## 📄 Description

save save workspace variables to .nh5 or .mat file.

## 💡 Examples

```matlab
A = ones(3, 4);
B = 'hello for open mat users';
save([tempdir(), 'example_load.mat'], 'A', 'B')
clear;
st = load([tempdir(), 'example_load.mat']);
who
st.A
st.B
clear
who
load([tempdir(), 'example_load.mat']);
who
A
B

```

append variables

```matlab
C = eye(3, 4);
save([tempdir(), 'example_load.mat'], 'C', '-append')
clear;
st = load([tempdir(), 'example_load.mat']);
who
st.A
st.B
st.C
clear
who
load([tempdir(), 'example_load.mat']);
who
A
B
C

```

compression

```matlab
C = eye(1000, 1000);
save([tempdir(), 'example_save_with_compression.mat'], 'C')
save([tempdir(), 'example_save_no_compression.mat'], 'C', '-nocompression')
with_compression = dir([tempdir(), 'example_save_with_compression.mat'])
no_compression = dir([tempdir(), 'example_save_no_compression.mat'])
```

## 🔗 See also

[load](/nelson/markdown/en/stream_manager/load.md), [savenh5](/nelson/markdown/en/hdf5/savenh5.md), [savemat](/nelson/markdown/en/matio/savemat.md).

## 🕔 History

| Version | 📄 Description  |
| ------- | --------------- |
| 1.0.0   | initial version |


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