1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"> 2 3<!--Converted with LaTeX2HTML 2018.3 (Released July 19, 2018) --> 4<HTML lang="EN"> 5<HEAD> 6<TITLE>query_polygon</TITLE> 7<META NAME="description" CONTENT="query_polygon"> 8<META NAME="keywords" CONTENT="subroutines"> 9<META NAME="resource-type" CONTENT="document"> 10<META NAME="distribution" CONTENT="global"> 11 12<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=utf-8"> 13<META NAME="viewport" CONTENT="width=device-width, initial-scale=1.0"> 14<META NAME="Generator" CONTENT="LaTeX2HTML v2018.3"> 15 <link rel='apple-touch-icon' sizes='180x180' href='images/favicons/apple-touch-icon.png?v=2017'> 16 <link rel='icon' type='image/png' sizes='32x32' href='images/favicons/favicon-32x32.png?v=2017'> 17 <link rel='icon' type='image/png' sizes='16x16' href='images/favicons/favicon-16x16.png?v=2017'> 18 <link rel='manifest' href='images/favicons/manifest.json?v=2017'> 19 <link rel='mask-icon' href='images/favicons/safari-pinned-tab.svg?v=2017' color='#5bbad5'> 20 <link rel='shortcut icon' href='images/favicons/favicon.ico?v=2017'> 21 <meta name='apple-mobile-web-app-title' content='HEALPix'> 22 <meta name='application-name' content='HEALPix'> 23 <meta name='msapplication-config' content='images/favicons/browserconfig.xml?v=2017'> 24 <meta name='theme-color' content='#ffffff'> 25 26<LINK REL="STYLESHEET" HREF="subroutines.css"> 27 28<LINK REL="next" HREF="sub_query_strip.htm"> 29<LINK REL="previous" HREF="sub_query_disc.htm"> 30<LINK REL="next" HREF="sub_query_strip.htm"> 31</HEAD> 32 33<body text="#000000" bgcolor="#FFFFFA"> 34 35<DIV CLASS="navigation"><!--Navigation Panel--> 36<A 37 HREF="sub_query_disc.htm"> 38<IMG WIDTH="63" HEIGHT="24" ALT="previous" SRC="prev.png"></A> 39<A 40 HREF="sub_HEALPix_F90_subroutines.htm"> 41<IMG WIDTH="26" HEIGHT="24" ALT="up" SRC="up.png"></A> 42<A 43 HREF="sub_query_strip.htm"> 44<IMG WIDTH="37" HEIGHT="24" ALT="next" SRC="next.png"></A> 45<A ID="tex2html450" 46 HREF="sub_TABLE_CONTENTS.htm"> 47<IMG WIDTH="65" HEIGHT="24" ALT="contents" SRC="contents.png"></A> 48<BR> 49<B> Previous:</B> <A 50 HREF="sub_query_disc.htm">query_disc</A> 51 52<B>Up:</B> <A 53 HREF="sub_HEALPix_F90_subroutines.htm">HEALPix/F90 subroutines</A> 54 55<B> Next:</B> <A 56 HREF="sub_query_strip.htm">query_strip</A> 57<B> Top:</B> <a href="main.htm">Main Page</a></DIV> 58<!--End of Navigation Panel--> 59 60<H1><A ID="SECTION7900"></A> 61<A ID="sub:query_polygon"></A> 62<BR> 63 64</H1> 65 66<P> 67<b><font size=+6><FONT COLOR="#CC0000">query_polygon</FONT></font></b><hr> 68<H3>Routine to find the index of all pixels enclosed in a polygon. The polygon should be convex, 69or have only one concave vertex. The edges should not intersect each other. 70The output indices can be either in the RING or NESTED scheme</H3> 71Location in HEALPix directory tree: <a href="https://sourceforge.net/p/healpix/code/1005/tree/trunk/src/f90/mod/pix_tools.F90"><b>src/f90/mod/pix_tools.F90</b></a> 72 73<P> 74<hr><h1>FORMAT </h1><blockquote><h3>call <FONT COLOR="#CC0000">query_polygon</FONT>( 75<A HREF="#sub:query_polygon:nside">nside</A>, <A HREF="#sub:query_polygon:vlist">vlist</A>, <A HREF="#sub:query_polygon:nv">nv</A>, <A HREF="#sub:query_polygon:listpix">listpix</A>, <A HREF="#sub:query_polygon:nlist">nlist</A>[, <A HREF="#sub:query_polygon:nest">nest</A>, <A HREF="#sub:query_polygon:inclusive">inclusive</A>] 76)</h3></blockquote> 77 78<P> 79<hr><H1>ARGUMENTS</H1> 80 81<TABLE CELLPADDING=3 BORDER="1"> 82<TR><TH ALIGN="LEFT" VALIGN="TOP" WIDTH=125><SPAN CLASS="textbf">name & dimensionality</SPAN></TH> 83<TH ALIGN="LEFT" VALIGN="TOP" WIDTH=25><SPAN CLASS="textbf">kind</SPAN></TH> 84<TH ALIGN="LEFT" VALIGN="TOP" WIDTH=50><SPAN CLASS="textbf">in/out</SPAN></TH> 85<TH ALIGN="LEFT" VALIGN="TOP" WIDTH=250><SPAN CLASS="textbf">description</SPAN></TH> 86</TR> 87<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125> </TD> 88<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25> </TD> 89<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50> </TD> 90<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250> </TD> 91</TR> 92<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125> 93nside<A ID="sub:query_polygon:nside"></A></TD> 94<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B</TD> 95<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 96<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>the <!-- MATH 97 $N_{\mathrm{side}}$ 98 --> 99<SPAN CLASS="MATH"><I>N</I><SUB>side</SUB></SPAN> parameter of the map.</TD> 100</TR> 101<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125>vlist<A ID="sub:query_polygon:vlist"></A>(1:3,0:*)</TD> 102<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>DP</TD> 103<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 104<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>cartesian vector pointing at polygon 105 respective vertices.</TD> 106</TR> 107<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125>nv<A ID="sub:query_polygon:nv"></A></TD> 108<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B</TD> 109<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 110<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>number of vertices, should be equal to 3 or larger.</TD> 111</TR> 112<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125>listpix<A ID="sub:query_polygon:listpix"></A>(0:*)</TD> 113<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B/ I8B</TD> 114<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>OUT</TD> 115<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>the index for all pixels enclosed in the triangle. Make sure that the size of the array is big enough to contain all pixels.</TD> 116</TR> 117<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125>nlist<A ID="sub:query_polygon:nlist"></A></TD> 118<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B/ I8B</TD> 119<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>OUT</TD> 120<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>The number of pixels listed in <TT>listpix</TT>.</TD> 121</TR> 122<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125>nest<A ID="sub:query_polygon:nest"></A> (OPTIONAL)</TD> 123<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B</TD> 124<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 125<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>The pixel indices are in the NESTED numbering scheme if nest=1, and in RING scheme otherwise.</TD> 126</TR> 127<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=125>inclusive<A ID="sub:query_polygon:inclusive"></A> (OPTIONAL)</TD> 128<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B</TD> 129<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 130<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=250>If set to 1, all the pixels overlapping 131 (even partially) 132 with the polygon are listed, otherwise only those whose 133 center lies within the polygon are listed.</TD> 134</TR> 135</TABLE> 136 137<P> 138<HR><H1>EXAMPLE:</H1> 139<tt>use <A HREF="sub_healpix_modules_module.htm#sub:healpix_modules">healpix_modules</A> 140<BR> 141real(dp), dimension(1:3,0:9) :: vertices 142<BR> 143vertices(:,0) = (/0.,0.,1./) ! +z 144<BR> 145vertices(:,1) = (/1.,0.,0./) ! +x 146<BR> 147vertices(:,2) = (/1.,1.,-1./) ! x+y-z 148<BR> 149vertices(:,3) = (/0.,1.,0./) ! +y 150<BR> 151<BR> 152call query_polygon(256,vertices,4,listpix,nlist,nest=0) 153<BR></tt> 154<blockquote> 155Returns the RING pixel index of all pixels in the polygon with vertices of 156cartesian coordinates (0,0,1), (1,0,0), (1,1,-1) and (0,1,0) in a <!-- MATH 157 $N_{\mathrm{side}}=256$ 158 --> 159<SPAN CLASS="MATH"><I>N</I><SUB>side</SUB>=256</SPAN> map. 160</blockquote> 161<hr><H1>MODULES & ROUTINES</H1><H3>This section lists the modules and routines used by <FONT COLOR="#CC0000">query_polygon</FONT>.</h3> 162 <DL COMPACT><DT> 163<B>isort</B> 164<DD>routine to sort integer number 165 <DT> 166<B><A HREF="sub_query_triangle.htm#sub:query_triangle">query_triangle</A></B> 167<DD>render the list of pixels enclosed 168 in a given triangle 169 <DT> 170<B><A HREF="sub_surface_triangle.htm#sub:surface_triangle">surface_triangle</A></B> 171<DD>computes the surface of a spherical triangle defined by 3 vertices 172 <DT> 173<B><A HREF="sub_vect_prod.htm#sub:vect_prod">vect_prod</A></B> 174<DD>routine to compute the vectorial product of two 3D vectors 175 </DL> 176 177<P> 178<hr><H1>RELATED ROUTINES</H1><h3>This section lists the routines related to <b><FONT COLOR="#CC0000">query_polygon</FONT></b></h3> 179 180 <DL COMPACT><DT> 181<B><A HREF="sub_pix2xxx_ang2xxx_vec2xxx_nes.htm#sub:pix_tools">pix2ang</A>, <A HREF="sub_pix2xxx_ang2xxx_vec2xxx_nes.htm#sub:pix_tools">ang2pix</A></B> 182<DD>convert between angle and pixel number. 183 <DT> 184<B><A HREF="sub_pix2xxx_ang2xxx_vec2xxx_nes.htm#sub:pix_tools">pix2vec</A>, <A HREF="sub_pix2xxx_ang2xxx_vec2xxx_nes.htm#sub:pix_tools">vec2pix</A></B> 185<DD>convert between a cartesian vector and pixel number. 186 <DT> 187<B><A HREF="sub_query_disc.htm#sub:query_disc">query_disc</A>, query_polygon,</B> 188<DD><DT> 189<B><A HREF="sub_query_strip.htm#sub:query_strip">query_strip</A>, <A HREF="sub_query_triangle.htm#sub:query_triangle">query_triangle</A></B> 190<DD>render the list of pixels enclosed 191 respectively in a given disc, polygon, latitude strip and triangle 192 <DT> 193<B><A HREF="sub_surface_triangle.htm#sub:surface_triangle">surface_triangle</A></B> 194<DD>computes the surface 195in steradians of a spherical triangle defined by 3 vertices 196 197<P> 198</DL> 199 200<P> 201 202<P> 203 204 205<P> 206 207<P> 208 209<DIV CLASS="navigation"><HR> 210<!--Navigation Panel--> 211<A 212 HREF="sub_query_disc.htm"> 213<IMG WIDTH="63" HEIGHT="24" ALT="previous" SRC="prev.png"></A> 214<A 215 HREF="sub_HEALPix_F90_subroutines.htm"> 216<IMG WIDTH="26" HEIGHT="24" ALT="up" SRC="up.png"></A> 217<A 218 HREF="sub_query_strip.htm"> 219<IMG WIDTH="37" HEIGHT="24" ALT="next" SRC="next.png"></A> 220<A ID="tex2html450" 221 HREF="sub_TABLE_CONTENTS.htm"> 222<IMG WIDTH="65" HEIGHT="24" ALT="contents" SRC="contents.png"></A> 223<BR> 224<B> Previous:</B> <A 225 HREF="sub_query_disc.htm">query_disc</A> 226 227<B>Up:</B> <A 228 HREF="sub_HEALPix_F90_subroutines.htm">HEALPix/F90 subroutines</A> 229 230<B> Next:</B> <A 231 HREF="sub_query_strip.htm">query_strip</A> 232<B> Top:</B> <a href="main.htm">Main Page</a></DIV> 233<!--End of Navigation Panel--> 234<ADDRESS> 235Version 3.50, 2018-12-10 236</ADDRESS> 237</BODY> 238</HTML> 239
