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  1. PO
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    <p>There is a number of problems. <strong>First</strong>, when you write</p> <pre><code>for K:=0 to Count-1 do Temperatures[K] := lstTemp.Items[K]; if (Temperatures[K] &gt; Max) then Max := Temperatures[K]; if (Temperatures[K] &lt; Min) then Min := Temperatures[K]; </code></pre> <p>you actually do</p> <pre><code>for K:=0 to Count-1 do Temperatures[K] := lstTemp.Items[K]; if (Temperatures[K] &gt; Max) then Max := Temperatures[K]; if (Temperatures[K] &lt; Min) then Min := Temperatures[K]; </code></pre> <p>which is nonsense. You want <em>all</em> these lines to be part of the <code>for</code> loop:</p> <pre><code>for K:=0 to Count-1 do begin Temperatures[K] := lstTemp.Items[K]; if (Temperatures[K] &gt; Max) then Max := Temperatures[K]; if (Temperatures[K] &lt; Min) then Min := Temperatures[K]; end; </code></pre> <p><strong>Second</strong>, in order for this algorithm to work, the initial value of <code>Min</code> (<code>Max</code>) needs to be larger (smaller) than the values in the list. This might work for <code>Max := 0</code>, but probably not for <code>Min := 0</code>. You need to set <code>Min</code> to a very large value before you run the loop, obviously. The best value you can use is the highest-possible signed 32-bit integer value, that is, 2^31 - 1, which is the value of the <code>MaxInt</code> constant.</p> <p><strong>Third</strong>,</p> <pre><code>Temperatures[K] := lstTemp.Items[K]; </code></pre> <p>is probably wrong. <code>Temperatures</code> is an array of <strong>integers</strong>, while <code>lstTemp.Items[K]</code> is a <strong>string</strong> (at least according to <code>StrToInt(lstTemp.Items[i])</code>), so you need</p> <pre><code>Temperatures[K] := StrToInt(lstTemp.Items[K]); </code></pre> <p><strong>Fourth</strong>, you declare <code>Average</code> as an <code>integer</code>, but it needs to be a floating-point number (obviously), like <code>real</code> or <code>double</code>.</p> <p><strong>Fifth</strong>,</p> <pre><code>edtAvg.Text:=IntToStr(Average); //Display Average edtAvg.Text:=IntToStr(Min); //Display Minimum Temp. edtAvg.Text:=IntToStr(Max); //Display Maximum Temp. </code></pre> <p>is not techncally incorrect, but will most likely not do what you want.</p> <p><strong>Sixth</strong>, although not an error, there is no need for you to initialise <code>Count</code> and <code>Average</code> to <code>0</code>. Finally, you only need a single <code>for</code> loop.</p>
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    1. PODelphi - Calculate Minimum Maximum and Average in items in a list
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    1. USAndreas Rejbrand
    1. USAndreas Rejbrand
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    1. VO
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      1. VTUpMod
    2. VO
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    1. CO`StrToInt` from a list of strings which could possibly have invalid integers :( How about `StrToIntDef`?
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      1. USJerry Dodge
    2. CO@Jerry: That depends on where the data comes from. In this case, the OP didn't even specify the type of the input data! (Probably a `TStrings`, though.)
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      1. USAndreas Rejbrand
    3. COAlso, only need one loop
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      1. US0909EM
 

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