Changes for page How to do with Linear Calibration?
Last modified by Mengting Qiu on 2024/09/02 17:23
From version 28.1
edited by Mengting Qiu
on 2024/09/02 17:23
on 2024/09/02 17:23
Change comment:
There is no comment for this version
To version 13.1
edited by Mengting Qiu
on 2024/09/02 16:18
on 2024/09/02 16:18
Change comment:
Uploaded new attachment "image-20240902161857-5.png", version {1}
Summary
-
Page properties (1 modified, 0 added, 0 removed)
-
Attachments (0 modified, 0 added, 11 removed)
- image-20240902163114-6.png
- image-20240902163527-7.png
- image-20240902164104-8.png
- image-20240902164156-9.png
- image-20240902164500-10.png
- image-20240902164503-11.png
- image-20240902164910-12.png
- image-20240902171200-13.png
- image-20240902171417-14.png
- image-20240902171627-15.png
- image-20240902171909-16.png
Details
- Page properties
-
- Content
-
... ... @@ -49,14 +49,14 @@ 49 49 When x=8 mA, y=2.5 meters 50 50 51 51 52 - **A more general formular:**52 +A more general formular: 53 53 54 -(% style="color:b lue" %)**Y=(y2-y1)/(x2-x1)* (x-x1) + y1**54 +(% style="color:#4f81bd" %)**Y=(y2-y1)/(x2-x1)* (x-x1) + y1** 55 55 56 56 57 57 Calibration Curve Schematic: 58 58 59 -[[image:image-20240902114541-1.png||height=" 336" width="596"]]59 +[[image:image-20240902114541-1.png||height="479" width="851"]] 60 60 61 61 62 62 == 2.2 Performing linear calibration curves in Excel == ... ... @@ -64,87 +64,13 @@ 64 64 65 65 In addition, we can also perform calibration curves in Excel and directly obtain linear equations by statistics of X and Y values. 66 66 67 -Citing the same example above, (% style="color:#4f81bd" %)**X**(%%) and (% style="color:#4f81bd" %)**Y**(%%). 68 68 69 69 70 -=== Step 1: Create chart === 71 71 72 72 73 -A simple spreadsheet with two columns: X values and Y values. 74 74 75 -[[image:image-20240902160516-1.png||height="404" width="561"]] 76 76 77 -* Start by selecting the data you want to plot in the chart. 78 -* First, select the X-Value column cell, then press the Ctrl key, and finally click the Y-value column cell. 79 79 80 -[[image:image-20240902160755-2.png||height="394" width="562"]] 81 - 82 -* Go to the "(% style="color:#4f81bd" %)**Insert**(%%)" TAB, navigate to the "(% style="color:#4f81bd" %)**Chart**(%%)" menu, and then select the first option in the "(% style="color:#4f81bd" %)**Scatter**(%%)" drop-down list. 83 -* A chart will appear with the data points in the two columns. 84 - 85 -[[image:image-20240902161202-3.png||height="453" width="824"]] 86 - 87 -* Right-click on one of the blue dots and select the (% style="color:#4f81bd" %)**"Add Trendline" **(%%)option. 88 - 89 -[[image:image-20240902161711-4.png||height="490" width="681"]] 90 - 91 -* A straight line will appear on the chart. 92 - 93 -On the right side of the screen, the Format Trendline menu will appear. Check the boxes next to (% style="color:#4f81bd" %)**"Show formulas on chart" **(%%)and (% style="color:#4f81bd" %)**"Show R-squared values on chart"**(%%). 94 - 95 -The R-squared value is a statistic that tells you how well the line fits the data. The best R-squared value is **1.000**, which means that every data point touches the line. 96 - 97 -Because the ideal data example is used, the R-squared value in this case is 1. 98 - 99 -As the difference between the data points and the line increases, the R-squared value decreases, with **0.000** being the lowest possible value. 100 - 101 -The equation is of the form (% style="color:blue" %)**"y = kx + b"**(%%),(% style="color:blue" %)** **(%%)where (% style="color:blue" %)**k**(%%) is the slope and (% style="color:blue" %)**b**(%%) is the y-intercept of the line. 102 - 103 -[[image:image-20240902161857-5.png||height="559" width="1103"]] 104 - 105 -* Calibration is complete. The user can customize the chart by editing the title and adding the axis title. 106 - 107 -[[image:image-20240902163527-7.png||height="349" width="656"]] 108 - 109 - 110 -=== Step 2: Calculate the line equation and R-squared statistic === 111 - 112 -* Write the (% style="color:#4f81bd" %)**Slope formula**(%%) in the formula bar according to the original x and y values statistics table. 113 - 114 -[[image:image-20240902164104-8.png||height="503" width="492"]] 115 - 116 -* Write (% style="color:#4f81bd" %)**Intercept formula**(%%) in the formula bar according to the original x and y value statistics table. 117 - 118 -[[image:image-20240902164156-9.png||height="525" width="488"]] 119 - 120 -* Write (% style="color:#4f81bd" %)**CORREL's squared formula**(%%) in the formula bar based on the original x and y statistics table. 121 - 122 -The CORREL function returns "R", so we have to square it to compute "R squared". 123 - 124 -[[image:image-20240902164503-11.png||height="523" width="743"]] 125 - 126 -* These values match those shown in the chart. 127 - 128 -[[image:image-20240902164910-12.png||height="420" width="897"]] 129 - 130 - 131 -=== Step 3: Set up formulas to quickly calculate X and Y values. === 132 - 133 - 134 -* The equation of the best fitting line is "Y-value = SLOPE * x-value + INTERCEPT", so the solution of "y-value" is obtained by multiplying X value and SLOPE, and then INTERCEPT is added. 135 - 136 -A simple formula table for calculating Y value automatically with input X value is obtained. 137 - 138 -[[image:image-20240902171627-15.png||height="440" width="754"]] 139 - 140 - 141 -* The X value based on the Y value is solved by subtracting INTERCEPT from the Y value and dividing the result by SLOPE: "x-value = (y-value-intercept)/SLOPE". 142 - 143 -A simple formula table for automatically calculating X value based on the input Y value is obtained. 144 - 145 -[[image:image-20240902171909-16.png||height="604" width="756"]] 146 - 147 - 148 148 = 3. Case examples = 149 149 150 150 ... ... @@ -168,12 +168,8 @@ 168 168 169 169 (% style="color:red" %)**Notice for Linear Calibrate:** 170 170 171 -(% style="color:red" %)**1. k(Slope) is very important, We can measure more points to calculate the most accuracy k. ** 97 +1. k(Slope) is very important, We can measure more points to calculate the most accuracy k. 98 +1. Make sure the mapping is linear, and choose two calibrate points as "far" as possible. 172 172 173 -(% style="color:red" %)**2. Make sure the mapping is linear, and choose two calibrate points as "far" as possible.** 174 174 175 - 176 - 177 - 178 - 179 179
- image-20240902163114-6.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -59.7 KB - Content
- image-20240902163527-7.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -25.8 KB - Content
- image-20240902164104-8.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -27.2 KB - Content
- image-20240902164156-9.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -24.4 KB - Content
- image-20240902164500-10.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -34.4 KB - Content
- image-20240902164503-11.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -34.4 KB - Content
- image-20240902164910-12.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -33.2 KB - Content
- image-20240902171200-13.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -64.5 KB - Content
- image-20240902171417-14.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -36.4 KB - Content
- image-20240902171627-15.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -37.9 KB - Content
- image-20240902171909-16.png
-
- Author
-
... ... @@ -1,1 +1,0 @@ 1 -XWiki.ting - Size
-
... ... @@ -1,1 +1,0 @@ 1 -54.6 KB - Content