<html><head></head><body><div style="color:#000; background-color:#fff; font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div tabindex="0" style="outline: none 0px; display: table; width: 1083px; box-sizing: border-box; padding-top: 12px; padding-left: 0px; font-family: "Helvetica Neue", "Segoe UI", Helvetica, Arial, "Lucida Grande", sans-serif; font-size: 13px;" id="yui_3_16_0_ym19_1_1492408494242_79860"><div style="display: table-cell; width: auto; word-wrap: break-word; word-break: break-word;" id="yui_3_16_0_ym19_1_1492408494242_79861"><div id="yui_3_16_0_ym19_1_1492408494242_79862"><div id="yui_3_16_0_ym19_1_1492408494242_79863"><div style="font-family: "Helvetica Neue", Helvetica, Arial, "Lucida Grande", sans-serif; font-size: 16px;" id="yui_3_16_0_ym19_1_1492408494242_79864"><div id="yui_3_16_0_ym19_1_1492408494242_79865"><span id="yui_3_16_0_ym19_1_1492408494242_79866">Dear All,</span></div><div id="yui_3_16_0_ym19_1_1492408494242_79867"><br clear="none" id="yui_3_16_0_ym19_1_1492408494242_79868"></div><div id="yui_3_16_0_ym19_1_1492408494242_79869"><span id="yui_3_16_0_ym19_1_1492408494242_79870">A better description of my problem is,</span></div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79871"><span id="yui_3_16_0_ym19_1_1492408494242_79872">I want to the difference between a model ppt output and observation data with different resolutions. The model has data over the both land and ocean whereas the observation has land only. But I only need the difference over land. I have regridded the model output <b id="yui_3_16_0_ym19_1_1492408494242_79975">successfully</b> but find it very difficult to get the difference between the two as this is my error message:</span></div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79873"><br clear="none" id="yui_3_16_0_ym19_1_1492408494242_79874"></div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79875">Error in gagchk: axis sizes are not the same</div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79876">Operation error: Incompatable grids</div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79877"> Error ocurred at column 8</div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79878">DISPLAY error: Invalid expression</div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79879"></div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79880"> Expression = w105-k1</div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79881"><br clear="none" id="yui_3_16_0_ym19_1_1492408494242_79882"></div><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79883">Thanks.</div><div id="yui_3_16_0_ym19_1_1492408494242_79884"></div><div id="yui_3_16_0_ym19_1_1492408494242_79885"> </div><div id="yui_3_16_0_ym19_1_1492408494242_79886"><div id="yui_3_16_0_ym19_1_1492408494242_79887"><div dir="ltr" id="yui_3_16_0_ym19_1_1492408494242_79888"><font size="2" id="yui_3_16_0_ym19_1_1492408494242_79889">Ugo Okoro</font></div></div></div></div></div></div></div></div></div></body></html>