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public:calculator:guides:dm15l_curve_fit [01/02/26 22:10 GMT] – [Method] johnpublic:calculator:guides:dm15l_curve_fit [12/02/26 21:01 GMT] (current) – [DM15L : Non-linear Curve Fit] john
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-====== DM15L : Non-linear Curve Fit ======+====== DM15L Non-linear Curve Fit ======
  
 ** Using DM15L/HP15C built-in L.R function to fit non-linear curves ** ** Using DM15L/HP15C built-in L.R function to fit non-linear curves **
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 The different curves require different treatment of the data to linearize, and the resulting coefficients may require treatment too. The different curves require different treatment of the data to linearize, and the resulting coefficients may require treatment too.
  
-===== Tl;DR =====+===== Tl;dr =====
  
-==== Method for Exponential ====+==== Method for Exponential==== 
 +**y = b.e<sup>ax</sup>** 
 + 
 +'' Ln(y) = a.x + Ln(b) ''
  
 |Enter Accumulation data | '' y<sub>i</sub> <key>'g'</key><key>'Ln'</key> x<sub>i</sub> <key>'∑+'</key>''| |Enter Accumulation data | '' y<sub>i</sub> <key>'g'</key><key>'Ln'</key> x<sub>i</sub> <key>'∑+'</key>''|
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 ==== Method for Logarithmic ==== ==== Method for Logarithmic ====
 +**y=a.ln(x)+b**
 +
 +''y = a.Ln(x) + b ''
  
 |Enter Accumulation data | '' y<sub>i</sub> <key>Enter</key> x<sub>i</sub> <key>'g'</key><key>Ln</key><key>'∑+'</key>''| |Enter Accumulation data | '' y<sub>i</sub> <key>Enter</key> x<sub>i</sub> <key>'g'</key><key>Ln</key><key>'∑+'</key>''|
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 ==== Method for Power ==== ==== Method for Power ====
 +**y=b.x<sup>a</sup>**
 +
 +'' Ln(y) = a.Ln(x) + Ln(b) ''
  
 |Enter Accumulation data |'' y<sub>i</sub> <key>'g'</key><key>Ln</key> x<sub>i</sub> <key>'g'</key><key>Ln</key><key>'∑+'</key>''| |Enter Accumulation data |'' y<sub>i</sub> <key>'g'</key><key>Ln</key> x<sub>i</sub> <key>'g'</key><key>Ln</key><key>'∑+'</key>''|
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 ==== Example Data ==== ==== Example Data ====
  
-|**x**|0.8|1.1|1.7|2.1|+
 |**y**|2.8|3.6|5.8|8.0| |**y**|2.8|3.6|5.8|8.0|
 +|**x**|0.8|1.1|1.7|2.1|
  
  
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 To estimate ''ŷ'' first find the ''Ln'' of ''x'' then use the <key>'f'</key><key>ŷ.r</key> To estimate ''ŷ'' first find the ''Ln'' of ''x'' then use the <key>'f'</key><key>ŷ.r</key>
  
-=== Method ===+==== Mechanism ====
  
  
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 ''x''<key>'g'</key><key>Ln</key><key>'f'</key><key>ŷ.r</key> ''x''<key>'g'</key><key>Ln</key><key>'f'</key><key>ŷ.r</key>
  
-=== Example Data ===+==== Example Data ====
  
-|**x**|0.8|1.7|2.6|4.9| 
 |**y**|1.5|1.7|1.8|2.1| |**y**|1.5|1.7|1.8|2.1|
 +|**x**|0.8|1.7|2.6|4.9|
 +
  
 <key>'f'</key><key>clear ∑</key> <key>'f'</key><key>clear ∑</key>
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-=== Method ===+==== Mechanism ====
  
 Accumulate using  Accumulate using 
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 ''x<key>'g'</key><key>Ln</key><key>'f'</key><key>ŷ.r</key><key>'e'<sup>x</sup></key>'' ''x<key>'g'</key><key>Ln</key><key>'f'</key><key>ŷ.r</key><key>'e'<sup>x</sup></key>''
  
-=== Example Data ===+==== Example Data ====
  
-|**x**|0.6|1.3|2.4|3.6| 
 |**y**|1.3|2.2|3.3|4.4| |**y**|1.3|2.2|3.3|4.4|
 +|**x**|0.6|1.3|2.4|3.6|
 +
  
 <key>'f'</key><key>clear ∑</key> <key>'f'</key><key>clear ∑</key>

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