<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">See the reference manual at <a href="http://www.ncl.ucar.edu/Document/Manuals/Ref_Manual/NclStatements.shtml#Loops">http://www.ncl.ucar.edu/Document/Manuals/Ref_Manual/NclStatements.shtml#Loops</a><div><br></div><div>Here's what it says about looping backwards:</div><div><br></div><div><span class="Apple-style-span" style="font-family: verdana, sans-serif; font-size: 13px; line-height: 16px; "><ul style="margin-top: 0px; margin-right: 0px; margin-bottom: 5px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; list-style-position: inside; "><p style="margin-top: 10px; margin-right: 0px; margin-bottom: 20px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; color: rgb(51, 51, 51); font-family: verdana, sans-serif; font-weight: normal; font-size: 10pt; line-height: 12pt; font-variant: normal; ">The following shows how to specify a loop with an explicit stride. The following form is also necessary to loop backwards. With this form, if start is greater than end, then the identifier is decremented by the stride value, which must always be positive. If the start is less than the end, then the identifier is incremented by the stride value.</p><div style="margin-top: 10px; margin-right: 0px; margin-bottom: 20px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; color: rgb(51, 51, 51); font-family: verdana, sans-serif; font-weight: normal; font-size: 10pt; line-height: 12pt; font-variant: normal; "><br class="webkit-block-placeholder"></div><pre style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; font-size: 10pt; line-height: 12pt; font-family: courier; border-top-style: solid; border-right-style: solid; border-bottom-style: solid; border-left-style: solid; border-top-width: 0px; border-right-width: 0px; border-bottom-width: 15px; border-left-width: 0px; border-top-color: transparent; border-right-color: transparent; border-bottom-color: transparent; border-left-color: transparent; text-indent: 0em; "> do <i style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; ">loop_identifier</i> = <i style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; ">scalar_start_expr</i> , <i style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; ">scalar_end_expr</i> , <i style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; "> scalar_stride_expr</i>
<i style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; "> statement list </i>
end do</pre></ul></span><div><br></div></div><div><br><div><div>On Oct 22, 2012, at 4:15 PM, Wen.J.Qu wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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<div><font face="Verdana"><font size="2">Hi, all</font></font></div>
<div><font size="2" face="Verdana"></font> </div>
<div><font size="2" face="Verdana">Would you please give some suggestions on how to
accomplish a loop with negative stride? Just as below?</font></div>
<div><font size="2" face="Verdana"></font> </div>
<div><font size="2" face="Verdana">Thanks a lot.</font></div>
<div><font size="2" face="Verdana"></font> </div>
<div>Shawn</div>
<div> </div>
<div> </div>
<div><font face="Verdana"><font size="2"></font></font> </div>
<div><font face="Verdana"><font size="2">**************************************************</font></font></div>
<div> do
i=lon90,lon180<br>
n588(year_index,day_index,i)=0.0<br>
do
j=lat80,lat10,-1<br>
if((h(year_index,day_index,j,i)/10.0 .le. 588.0) .and.
(h(year_index,day_index,j-1,i)/10.0 .le.
588.0))then<br>
n588(year_index,day_index,i)=j<br>
break<br>
end if<br>
end do<br> end do</div>
<div><font face="Verdana"><font size="2">**************************************************</font></font></div><font face="Verdana">
<div><font size="2"></font> </div>
<div align="left"><font size="2">
<hr style="WIDTH: 122px; HEIGHT: 2px" size="2">
</font></div>
<div><font color="#c0c0c0"><font size="2">Wen.J.Qu</font></font></div><font color="#c0c0c0">
</font><div><font color="#c0c0c0"><font size="2">2012-10-22</font></font></div></font></div>
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