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>generate_beam</TITLE> 7<META NAME="description" CONTENT="generate_beam"> 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_get_card.htm"> 29<LINK REL="previous" HREF="sub_gaussbeam.htm"> 30<LINK REL="next" HREF="sub_get_card.htm"> 31</HEAD> 32 33<body text="#000000" bgcolor="#FFFFFA"> 34 35<DIV CLASS="navigation"><!--Navigation Panel--> 36<A 37 HREF="sub_gaussbeam.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_get_card.htm"> 44<IMG WIDTH="37" HEIGHT="24" ALT="next" SRC="next.png"></A> 45<A ID="tex2html358" 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_gaussbeam.htm">gaussbeam</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_get_card.htm">get_card</A> 57<B> Top:</B> <a href="main.htm">Main Page</a></DIV> 58<!--End of Navigation Panel--> 59 60<H1><A ID="SECTION3300"></A> 61<A ID="sub:generate_beam"></A> 62<BR> 63 64</H1> 65 66<P> 67<b><font size=+6><FONT COLOR="#CC0000">generate_beam</FONT></font></b><hr> 68<H3>This routine generates the beam window function in multipole space. It is 69 either a gaussian parametrized by its FWHM in arcmin in real space, or it is 70 read from an external file.</H3> 71Location in HEALPix directory tree: <a href="https://sourceforge.net/p/healpix/code/1005/tree/trunk/src/f90/mod/alm_tools.F90"><b>src/f90/mod/alm_tools.F90</b></a> 72 73<P> 74<hr><h1>FORMAT </h1><blockquote><h3>call <FONT COLOR="#CC0000">generate_beam</FONT>( 75<A HREF="#sub:generate_beam:fwhm_arcmin">fwhm_arcmin</A>, <A HREF="#sub:generate_beam:lmax">lmax</A>, <A HREF="#sub:generate_beam:beam">beam</A><i><font color="#224422">[, <A HREF="#sub:generate_beam:beam_file">beam_file</A>]</font></i> 76)</h3></blockquote> 77Arguments appearing in <i><font color="#224422">italic</font></i> are 78optional. 79 80<P> 81<hr><H1>ARGUMENTS</H1> 82 83<TABLE CELLPADDING=3 BORDER="1"> 84<TR><TH ALIGN="LEFT" VALIGN="TOP" WIDTH=200><SPAN CLASS="textbf">name & dimensionality</SPAN></TH> 85<TH ALIGN="LEFT" VALIGN="TOP" WIDTH=25><SPAN CLASS="textbf">kind</SPAN></TH> 86<TH ALIGN="LEFT" VALIGN="TOP" WIDTH=50><SPAN CLASS="textbf">in/out</SPAN></TH> 87<TH ALIGN="LEFT" VALIGN="TOP" WIDTH=175><SPAN CLASS="textbf">description</SPAN></TH> 88</TR> 89<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=200> </TD> 90<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25> </TD> 91<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50> </TD> 92<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=175> </TD> 93</TR> 94<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=200> 95fwhm_arcmin<A ID="sub:generate_beam:fwhm_arcmin"></A></TD> 96<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>DP</TD> 97<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 98<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=175>fwhm size of the gaussian beam in arcminutes.</TD> 99</TR> 100<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=200>lmax<A ID="sub:generate_beam:lmax"></A></TD> 101<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>I4B</TD> 102<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 103<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=175>maximum <SPAN CLASS="MATH"><IMG STYLE="height: 1.69ex; vertical-align: -0.10ex; " SRC="sub_img21.png" 104 ALT="$\ell$"></SPAN> value of the window function.</TD> 105</TR> 106<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=200>beam<A ID="sub:generate_beam:beam"></A>(0:lmax,1:p)</TD> 107<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>DP</TD> 108<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>OUT</TD> 109<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=175>beam window function generated. The second index runs form 1:1 for temperature only, and 1:3 for polarisation. In the latter case, 1=T, 2=E, 3=B.</TD> 110</TR> 111<TR><TD ALIGN="LEFT" VALIGN="TOP" WIDTH=200><i><font color="#224422">beam_file</font></i><A ID="sub:generate_beam:beam_file"></A>(LEN=<tt>filenamelen</tt>) (OPTIONAL)</TD> 112<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=25>CHR</TD> 113<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=50>IN</TD> 114<TD ALIGN="LEFT" VALIGN="TOP" WIDTH=175>name of the file containing 115the (non necessarily gaussian) window function <SPAN CLASS="MATH"><IMG STYLE="height: 2.04ex; vertical-align: -0.45ex; " SRC="sub_img78.png" 116 ALT="$B_\ell$"></SPAN> of a circular beam. If present, it will override 117the argument <TT>fwhm_arcmin</TT>. If fewer columns than requested are found in 118the file, missing colums will duplicate the existing ones (based on the 119assumption that <SPAN CLASS="MATH"><IMG STYLE="height: 2.04ex; vertical-align: -0.45ex; " SRC="sub_img78.png" 120 ALT="$B_\ell$"></SPAN> is the same in T, E and B). Supports the <TT>fitsio</TT> 'Extended Filename 121Syntax' (see <A HREF="#sub:generate_beam:ex">examples below</A>).</TD> 122</TR> 123</TABLE> 124 125<P> 126<HR><H1>EXAMPLE:</H1> 127<tt>use <A HREF="sub_healpix_modules_module.htm#sub:healpix_modules">healpix_modules</A> 128<BR> 129real(dp), dimension(0:1024, 1:3) :: gb0, b1, b2, b3 130<BR> 131call generate_beam(5.0_dp, 1024, gb0) 132<BR> 133call generate_beam(0_dp, 1024, b1, beam_file='file.fits') 134<BR> 135call generate_beam(0_dp, 1024, b2, beam_file='file.fits[col 1]') 136<BR> 137call generate_beam(0_dp, 1024, b3, beam_file='file.fits[col 1; 2=0; 3=0]') 138<BR></tt> 139<blockquote><TT>gb0</TT> will contain the window function of a gaussian beam of FWHM = 5 arcmin, for <!-- MATH 140 $\ell 141\leq 1024$ 142 --> 143<SPAN CLASS="MATH"><IMG STYLE="height: 1.98ex; vertical-align: -0.41ex; " SRC="sub_img116.png" 144 ALT="$\ell 145\leq 1024$"></SPAN>. 146<BR> 147<TT>b1</TT> will contain the first 3 columns (if available) of <TT>file.fits</TT>. If 148the file contains only two columns, then <TT>b1(:,3) = b1(:,2)</TT>, and 149if it contains a single column, then <TT>b1(:,3) = b1(:,2) = b1(:,1)</TT>. 150<BR> 151<TT>b2</TT> will be 152based on a virtual FITS file containg only the first column of <TT>file.fits</TT>, 153and we will have <TT>b2(:,3) = b2(:,2) = b2(:,1)</TT>. 154<BR> 155Finally <TT>b3</TT> will read a 156virtual FITS file in which the first column is the same as in <TT>file.fits</TT>, 157while the columns 2 and 3 are set to 0. Therefore <TT>b3(:,3) = b3(:,2) = 0</TT>. 158<A ID="sub:generate_beam:ex"></A></blockquote> 159 160<P> 161<hr><H1>MODULES & ROUTINES</H1><H3>This section lists the modules and routines used by <FONT COLOR="#CC0000">generate_beam</FONT>.</h3> 162 <DL COMPACT><DT> 163<B><SPAN CLASS="textbf">alm_tools</SPAN></B> 164<DD>module, containing: 165 <DT> 166<B><A HREF="sub_gaussbeam.htm#sub:gaussbeam">gaussbeam</A></B> 167<DD>routine to generate a gaussian beam 168 </DL> 169 170<P> 171<hr><H1>RELATED ROUTINES</H1><h3>This section lists the routines related to <b><FONT COLOR="#CC0000">generate_beam</FONT></b></h3> 172 173 <DL COMPACT><DT> 174<B><A HREF="sub_create_alm.htm#sub:create_alm">create_alm</A></B> 175<DD>Routine to create <SPAN CLASS="MATH"><IMG STYLE="height: 1.46ex; vertical-align: -0.45ex; " SRC="sub_img6.png" 176 ALT="$a_{\ell m}$"></SPAN> 177 coefficients using <FONT COLOR="#CC0000">generate_beam</FONT>. 178 <DT> 179<B><A HREF="sub_alter_alm.htm#sub:alter_alm">alter_alm</A></B> 180<DD>Routine to alter <SPAN CLASS="MATH"><IMG STYLE="height: 1.46ex; vertical-align: -0.45ex; " SRC="sub_img6.png" 181 ALT="$a_{\ell m}$"></SPAN> 182 coefficients using <FONT COLOR="#CC0000">generate_beam</FONT>. 183 <DT> 184<B><A HREF="sub_pixel_window.htm#sub:pixel_window">pixel_window</A></B> 185<DD>Routine returning a pixel 186 window function. 187 </DL> 188 189<P> 190 191<P> 192 193 194<P> 195 196<P> 197 198<DIV CLASS="navigation"><HR> 199<!--Navigation Panel--> 200<A 201 HREF="sub_gaussbeam.htm"> 202<IMG WIDTH="63" HEIGHT="24" ALT="previous" SRC="prev.png"></A> 203<A 204 HREF="sub_HEALPix_F90_subroutines.htm"> 205<IMG WIDTH="26" HEIGHT="24" ALT="up" SRC="up.png"></A> 206<A 207 HREF="sub_get_card.htm"> 208<IMG WIDTH="37" HEIGHT="24" ALT="next" SRC="next.png"></A> 209<A ID="tex2html358" 210 HREF="sub_TABLE_CONTENTS.htm"> 211<IMG WIDTH="65" HEIGHT="24" ALT="contents" SRC="contents.png"></A> 212<BR> 213<B> Previous:</B> <A 214 HREF="sub_gaussbeam.htm">gaussbeam</A> 215 216<B>Up:</B> <A 217 HREF="sub_HEALPix_F90_subroutines.htm">HEALPix/F90 subroutines</A> 218 219<B> Next:</B> <A 220 HREF="sub_get_card.htm">get_card</A> 221<B> Top:</B> <a href="main.htm">Main Page</a></DIV> 222<!--End of Navigation Panel--> 223<ADDRESS> 224Version 3.50, 2018-12-10 225</ADDRESS> 226</BODY> 227</HTML> 228
