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HOME > Monitoring_and_Data > Oceanic and Atmospheric Data > Reanalysis: Atmospheric Data > wgrib2-stats, -mmax, -min

### Introduction

The -stats option writes a statistical summary of the field into the inventory. The -max option writes the maximum value and the -min option writes the minimum. These option are useful for quickly determining if the field has reasonable numbers.

### Usage

```-stats
-max
-min
```

### Example

```\$ wgrib2 test.grb2 -stats
1:0:ndata=65160:undef=0:mean=83.8696:min=-428.1:max=317.8

ndata = number of grid points
undef = number of grid points with an undefined value
mean = grid point average (not area weighted)
min = minimum value
max = maximum value

\$ wgrib2 test.grb2 -max
1:0:max=317.8

\$ wgrib2 test.grb2 -min
1:0:min=-428.1

```
The -stats option can be combined with the -undefine option to produce statistics for a box.
```\$ wgrib2 test.grb2 -stats
1:4:ndata=10512:undef=0:mean=77.5081:min=-370:max=340.2:cos_wt_mean=97.267
```
produces the global statistics. By setting grid points to undefined, we can produce the statistics for a box.
```\$ wgrib2 test.grb2 -undefine outobx 0:90 -10:10 -stats
1:4:ndata=10512:undef=10179:mean=79.8829:min=41:max=144:cos_wt_mean=79.8688
```
Note, if we reverse the order of the -stats and -undefine options, we get the global mean. That is because the -stats option is excuted before the -undefine options. \$ wgrib2 test.grb2 -stats -undefine out-box 0:10 -10:10 1:4:ndata=10512:undef=0:mean=77.5081:min=-370:max=340.2:cos_wt_mean=97.267

If all the data are undefined, the -stats option will produce values of zero for the the mean, min and max. The -min and -max options will yield a text string of "undefined".