<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Not sure if the space between the 'a' and the '[5]' is causing your problem but worth a try...</div><div><br class="webkit-block-placeholder"></div><div>Gareth.</div><br><div><div>On 21/12/2007, at 12:47 PM, Joseph Walrath wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: collapse; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; ">Hello,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "> <br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; ">I am having some trouble the with Analyze function. I have a simple 4th order polynomial function: </div><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "></p><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "> <span style="color: rgb(0, 0, 204); "><br></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "><span style="color: rgb(0, 0, 204); "> function</span> SlopeFunction;</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; color: rgb(0, 0, 204); ">begin</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; color: rgb(204, 0, 0); "> <span style="color: rgb(0, 0, 0); "><span style="color: rgb(204, 0, 204); "> y</span>:= <span style="color: rgb(204, 0, 204); ">a</span>[1] + <span style="color: rgb(204, 0, 204); ">a</span>[2] + 2.0*<span style="color: rgb(204, 0, 204); "> a</span>[4]*(<span style="color: rgb(204, 0, 204); ">x</span>-<span style="color: rgb(204, 0, 204); ">a</span>[3]) + 3.0*<span style="color: rgb(204, 0, 204); ">a</span> [5]*(<span style="color: rgb(204, 0, 204); ">x</span> -<span style="color: rgb(204, 0, 204); ">a</span>[3])^2</span><br></div><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; min-height: 12px; "><span style="white-space: pre; "> </span><br class="webkit-block-placeholder"></p><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "><span style="white-space: pre; "> </span>+ 4.0*<span style="color: rgb(204, 0, 204); "> a</span>[6]*(<span style="color: rgb(204, 0, 204); ">x</span>-<span style="color: rgb(204, 0, 204); "> a</span>[3])^3 + 5.0*<span style="color: rgb(204, 0, 204); ">a</span>[7]*(<span style="color: rgb(204, 0, 204); ">x</span> -<span style="color: rgb(204, 0, 204); ">a</span>[3])^4 ;</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; color: rgb(0, 0, 204); ">end<span style="color: rgb(0, 0, 0); "> ;</span></div><div><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "> The parameters are always defined with SetParameterProperties. However, I get NAN as an answer for both x and y.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "> <br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "><span style="color: rgb(0, 153, 51); ">Analyze</span>(<span style="color: rgb(0, 0, 204); "> function</span> SlopeFunction, type <span style="color: rgb(204, 102, 0); ">FindMaximum</span>, useFittedParameters <span style="color: rgb(204, 102, 0); ">false</span>, tabulateResults <span style="color: rgb(204, 102, 0); "> true</span>,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 9px/normal Monaco; "><span style="white-space: pre; "> </span>parameter 0, xMin -10, xMax 10, subintervals 4); </div><div><br></div><div>Anyone had problems with this routine?</div><div><br></div><div>Thanks much</div><div>Joe</div><font color="#888888"></font></span><font color="#888888"></font><br>-- <br>Joseph Walrath, MD<br>Departments of Ophthalmology <br>Columbia University, Edward S. Harkness Eye Institute<br>St. Vincent's Catholic Medical Center</blockquote></div><br></body></html>