1cdf0e10cSrcweir<?xml version="1.0" encoding="UTF-8"?>
2cdf0e10cSrcweir
3d33d0967SAndrew Rist<!--***********************************************************
410be1ba9Smseidel *
5d33d0967SAndrew Rist * Licensed to the Apache Software Foundation (ASF) under one
6d33d0967SAndrew Rist * or more contributor license agreements.  See the NOTICE file
7d33d0967SAndrew Rist * distributed with this work for additional information
8d33d0967SAndrew Rist * regarding copyright ownership.  The ASF licenses this file
9d33d0967SAndrew Rist * to you under the Apache License, Version 2.0 (the
10d33d0967SAndrew Rist * "License"); you may not use this file except in compliance
11d33d0967SAndrew Rist * with the License.  You may obtain a copy of the License at
1210be1ba9Smseidel *
13d33d0967SAndrew Rist *   http://www.apache.org/licenses/LICENSE-2.0
1410be1ba9Smseidel *
15d33d0967SAndrew Rist * Unless required by applicable law or agreed to in writing,
16d33d0967SAndrew Rist * software distributed under the License is distributed on an
17d33d0967SAndrew Rist * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
18d33d0967SAndrew Rist * KIND, either express or implied.  See the License for the
19d33d0967SAndrew Rist * specific language governing permissions and limitations
20d33d0967SAndrew Rist * under the License.
2110be1ba9Smseidel *
22d33d0967SAndrew Rist ***********************************************************-->
23d33d0967SAndrew Rist
24cdf0e10cSrcweir<helpdocument version="1.0">
25cdf0e10cSrcweir<meta>
26cdf0e10cSrcweir<topic id="textsbasicshared03080101xml" indexer="include" status="PUBLISH">
27cdf0e10cSrcweir<title id="tit" xml-lang="en-US">Atn Function [Runtime]</title>
28cdf0e10cSrcweir<filename>/text/sbasic/shared/03080101.xhp</filename>
29cdf0e10cSrcweir</topic>
30cdf0e10cSrcweir</meta>
31cdf0e10cSrcweir<body>
32cdf0e10cSrcweir<section id="atn">
33*734551d2Smseidel<bookmark xml-lang="en-US" branch="index" id="bm_id3150616">
34*734551d2Smseidel<bookmark_value>Atn function</bookmark_value>
35cdf0e10cSrcweir</bookmark>
36cdf0e10cSrcweir<paragraph role="heading" id="hd_id3150616" xml-lang="en-US" level="1" l10n="U" oldref="1"><link href="text/sbasic/shared/03080101.xhp" name="Atn Function [Runtime]">Atn Function [Runtime]</link></paragraph>
37cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3149346" xml-lang="en-US" l10n="U" oldref="2">Trigonometric function that returns the arctangent of a numeric expression. The return value is in the range -Pi/2 to +Pi/2.</paragraph>
38cdf0e10cSrcweir</section>
39cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3143271" xml-lang="en-US" l10n="U" oldref="3">The arctangent is the inverse of the tangent function. The Atn Function returns the angle "Alpha", expressed in radians, using the tangent of this angle. The function can also return the angle "Alpha" by comparing the ratio of the length of the side that is opposite of the angle to the length of the side that is adjacent to the angle in a right-angled triangle.</paragraph>
40cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3145315" xml-lang="en-US" l10n="U" oldref="4">Atn(side opposite the angle/side adjacent to angle)= Alpha</paragraph>
41cdf0e10cSrcweir<paragraph role="heading" id="hd_id3149669" xml-lang="en-US" level="2" l10n="U" oldref="5">Syntax:</paragraph>
42cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3148947" xml-lang="en-US" l10n="U" oldref="6">Atn (Number)</paragraph>
43cdf0e10cSrcweir<paragraph role="heading" id="hd_id3148664" xml-lang="en-US" level="2" l10n="U" oldref="7">Return value:</paragraph>
44cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3150359" xml-lang="en-US" l10n="U" oldref="8">Double</paragraph>
45cdf0e10cSrcweir<paragraph role="heading" id="hd_id3148798" xml-lang="en-US" level="2" l10n="U" oldref="9">Parameters:</paragraph>
46cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3156212" xml-lang="en-US" l10n="U" oldref="10">
47cdf0e10cSrcweir<emph>Number:</emph> Any numerical expression that represents the ratio of two sides of a right triangle. The Atn function returns the corresponding angle in radians (arctangent).</paragraph>
48cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3153192" xml-lang="en-US" l10n="U" oldref="11">To convert radians to degrees, multiply radians by 180/pi.</paragraph>
49cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3147230" xml-lang="en-US" l10n="U" oldref="12">degree=(radian*180)/pi</paragraph>
50cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3125864" xml-lang="en-US" l10n="U" oldref="13">radian=(degree*pi)/180</paragraph>
51cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3159252" xml-lang="en-US" l10n="U" oldref="14">Pi is here the fixed circle constant with the rounded value 3.14159.</paragraph>
52cdf0e10cSrcweir<embed href="text/sbasic/shared/00000003.xhp#errorcode"/>
53cdf0e10cSrcweir<embed href="text/sbasic/shared/00000003.xhp#err5"/>
54cdf0e10cSrcweir<paragraph role="heading" id="hd_id3153142" xml-lang="en-US" level="2" l10n="U" oldref="15">Example:</paragraph>
55cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3146985" xml-lang="en-US" l10n="U" oldref="16">REM The following example calculates for a right-angled triangle</paragraph>
56cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3145750" xml-lang="en-US" l10n="U" oldref="17">REM the angle Alpha from the tangent of the angle Alpha:</paragraph>
57cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3146975" xml-lang="en-US" l10n="U" oldref="18">Sub ExampleATN</paragraph>
58cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3151112" xml-lang="en-US" l10n="U" oldref="19">REM rounded Pi = 3.14159 is a predefined constant</paragraph>
59cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3159156" xml-lang="en-US" l10n="U" oldref="20">Dim d1 As Double</paragraph>
60cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3147435" xml-lang="en-US" l10n="U" oldref="21">Dim d2 As Double</paragraph>
61cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3149262" xml-lang="en-US" l10n="U" oldref="22">d1 = InputBox$ ("Enter the length of the side adjacent to the angle: ","Adjacent")</paragraph>
62cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3149482" xml-lang="en-US" l10n="U" oldref="23">d2 = InputBox$ ("Enter the length of the side opposite the angle: ","Opposite")</paragraph>
63cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3155415" xml-lang="en-US" l10n="U" oldref="24">Print "The Alpha angle is"; (atn (d2/d1) * 180 / Pi); " degrees"</paragraph>
64cdf0e10cSrcweir<paragraph role="paragraph" id="par_id3149959" xml-lang="en-US" l10n="U" oldref="25">End Sub</paragraph>
65cdf0e10cSrcweir</body>
66cdf0e10cSrcweir</helpdocument>
67