<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">There was a similar question I found in the archives, response from Mary below. &nbsp;<a href="https://www.ncl.ucar.edu/Support/talk_archives/2009/1643.html" class="">https://www.ncl.ucar.edu/Support/talk_archives/2009/1643.html</a><div class=""><br class=""></div><div class=""><div class="">“</div><div class=""><span style="font-family: -webkit-standard;" class="">"get_res_value" is an internal routine that is not meant</span><span style="font-family: -webkit-standard;" class="">&nbsp;</span><span style="font-family: -webkit-standard;" class="">in general for users.</span><span style="font-family: -webkit-standard;" class="">&nbsp;</span></div><p style="font-family: -webkit-standard;" class="">What it does is looks at logical variable to see if it is True *and*&nbsp;<br class="">if the given attribute is attached to it. If it is, then it returns&nbsp;<br class="">that attribute's value. If not, then what's returned is the third&nbsp;<br class="">argument of "get_res_value".&nbsp;<br class=""></p><p style="font-family: -webkit-standard;" class="">So:&nbsp;<br class=""></p><p style="font-family: -webkit-standard;" class="">&nbsp;&nbsp;&nbsp;useT = get_res_value(opts,"useTime",0)&nbsp;<br class=""></p><p style="font-family: -webkit-standard;" class="">is the equivalent of:&nbsp;<br class=""></p><p style="font-family: -webkit-standard;" class="">&nbsp;&nbsp;&nbsp;if(opts.and.isatt(opts,"useTime")) then&nbsp;<br class="">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;useT = opts@useTime&nbsp;<br class="">&nbsp;&nbsp;&nbsp;else&nbsp;<br class="">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;useT = 0&nbsp;<br class="">&nbsp;&nbsp;&nbsp;end if&nbsp;<br class=""></p><div class="">“</div><div class=""><br class=""></div><div class="">get_res_value() deletes the obtained attribute, while get_res_value_keep() does not. &nbsp;&nbsp;</div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">Alan.&nbsp;</div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""><div class=""><br class=""><div class="">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-stroke-width: 0px;"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">##############################<br class="">Alan Brammer,<div class="">Post-Doc Researcher</div><div class=""><br class=""></div><div class="">Department of Atmospheric and&nbsp;Environmental Sciences,<br class="">University at Albany,&nbsp;State University of New&nbsp;York,&nbsp;Albany, NY, 12222<div class=""><a href="mailto:abrammer@albany.edu" class="">abrammer@albany.edu</a><br class="">##############################</div></div></div></span></div></div>
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<br class=""><div><blockquote type="cite" class=""><div class="">On 14 Feb 2016, at 23:25, Lijun Diao &lt;<a href="mailto:ljdiao@gmail.com" class="">ljdiao@gmail.com</a>&gt; wrote:</div><br class="Apple-interchange-newline"><div class="">
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<div class="">Hi, ncl talk forum:</div>
<div class="">&nbsp;</div>
<div class="">When I was reading shapefile_utils.ncl, I came across get_res_value_keep 
function. I could not find explanation of such function. Where can I find some 
info about this function of its usage or meaning?</div>
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<div class="">thanks,</div>
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<div style="font-size: 12pt; font-family: Calibri;" class="">-----------------------------------------------------------------------------<br class="">Lijun 
Diao<br class=""><a href="mailto:ldiao@uh.edu" class="">ldiao@uh.edu</a><br class="">Research Assistant<br class="">Department of Earth &amp; 
Atmospheric Sciences<br class="">University of Houston<br class="">4800 Calhoun RD., Bldg. 
S&amp;R1-312<br class="">Houston, TX 77204-5007</div></div></div></div>
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