Romberg-Integration relative error












0












$begingroup$


How can I check if the relative error of two successive diagonal elements is smaller than e.g. $10^{-3}$?



$leftvert frac{T_{1,2}-T_{1,3}}{T_{1,3}}rightvert<0.001$



for a Romberg Tableau of this form



$begin{array}{cccccc}
T_{1,1}\
&backslash\
T_{2,2}&-&T_{1,2}\
&backslash&&backslash\
T_{3,3}&-&T_{2,3}&-&T_{1,3}\
&backslash&&backslash&&backslash\
end{array}$



I am using for $h=frac{b-a}{N_i}$ with $a$, $b$ as integral limits and $N_i=2^i$, $i=1,...$ as Romberg sequence.



I am using the trapezoidal sum to compute



$T_{i,1}=T(h_i)=frac{h_i}{2}left(f(a)+f(b)+sum_{j=1}^{N_i-1}f(a+jcdot h_i)right)$



and all other elements are computed with the following formula:



$T_{(j,j+k)}(f)=T_{(j+1,j+k)}(f)+frac{T_{(j+1,k+1)}(f)-T_{(j,j+k-1)}(f)}{left(frac{h_j}{h_{j+k}}right)^2-1}$



Thank you in advance.










share|cite|improve this question











$endgroup$












  • $begingroup$
    What are the trapezoidal and what the Simpson sums? Are these the diagonals? Is the difference that you want to estimate between trapezoidal sums?
    $endgroup$
    – LutzL
    Jan 26 at 17:15










  • $begingroup$
    I think/hope I added all the missing information.
    $endgroup$
    – baxbear
    Jan 27 at 2:12
















0












$begingroup$


How can I check if the relative error of two successive diagonal elements is smaller than e.g. $10^{-3}$?



$leftvert frac{T_{1,2}-T_{1,3}}{T_{1,3}}rightvert<0.001$



for a Romberg Tableau of this form



$begin{array}{cccccc}
T_{1,1}\
&backslash\
T_{2,2}&-&T_{1,2}\
&backslash&&backslash\
T_{3,3}&-&T_{2,3}&-&T_{1,3}\
&backslash&&backslash&&backslash\
end{array}$



I am using for $h=frac{b-a}{N_i}$ with $a$, $b$ as integral limits and $N_i=2^i$, $i=1,...$ as Romberg sequence.



I am using the trapezoidal sum to compute



$T_{i,1}=T(h_i)=frac{h_i}{2}left(f(a)+f(b)+sum_{j=1}^{N_i-1}f(a+jcdot h_i)right)$



and all other elements are computed with the following formula:



$T_{(j,j+k)}(f)=T_{(j+1,j+k)}(f)+frac{T_{(j+1,k+1)}(f)-T_{(j,j+k-1)}(f)}{left(frac{h_j}{h_{j+k}}right)^2-1}$



Thank you in advance.










share|cite|improve this question











$endgroup$












  • $begingroup$
    What are the trapezoidal and what the Simpson sums? Are these the diagonals? Is the difference that you want to estimate between trapezoidal sums?
    $endgroup$
    – LutzL
    Jan 26 at 17:15










  • $begingroup$
    I think/hope I added all the missing information.
    $endgroup$
    – baxbear
    Jan 27 at 2:12














0












0








0





$begingroup$


How can I check if the relative error of two successive diagonal elements is smaller than e.g. $10^{-3}$?



$leftvert frac{T_{1,2}-T_{1,3}}{T_{1,3}}rightvert<0.001$



for a Romberg Tableau of this form



$begin{array}{cccccc}
T_{1,1}\
&backslash\
T_{2,2}&-&T_{1,2}\
&backslash&&backslash\
T_{3,3}&-&T_{2,3}&-&T_{1,3}\
&backslash&&backslash&&backslash\
end{array}$



I am using for $h=frac{b-a}{N_i}$ with $a$, $b$ as integral limits and $N_i=2^i$, $i=1,...$ as Romberg sequence.



I am using the trapezoidal sum to compute



$T_{i,1}=T(h_i)=frac{h_i}{2}left(f(a)+f(b)+sum_{j=1}^{N_i-1}f(a+jcdot h_i)right)$



and all other elements are computed with the following formula:



$T_{(j,j+k)}(f)=T_{(j+1,j+k)}(f)+frac{T_{(j+1,k+1)}(f)-T_{(j,j+k-1)}(f)}{left(frac{h_j}{h_{j+k}}right)^2-1}$



Thank you in advance.










share|cite|improve this question











$endgroup$




How can I check if the relative error of two successive diagonal elements is smaller than e.g. $10^{-3}$?



$leftvert frac{T_{1,2}-T_{1,3}}{T_{1,3}}rightvert<0.001$



for a Romberg Tableau of this form



$begin{array}{cccccc}
T_{1,1}\
&backslash\
T_{2,2}&-&T_{1,2}\
&backslash&&backslash\
T_{3,3}&-&T_{2,3}&-&T_{1,3}\
&backslash&&backslash&&backslash\
end{array}$



I am using for $h=frac{b-a}{N_i}$ with $a$, $b$ as integral limits and $N_i=2^i$, $i=1,...$ as Romberg sequence.



I am using the trapezoidal sum to compute



$T_{i,1}=T(h_i)=frac{h_i}{2}left(f(a)+f(b)+sum_{j=1}^{N_i-1}f(a+jcdot h_i)right)$



and all other elements are computed with the following formula:



$T_{(j,j+k)}(f)=T_{(j+1,j+k)}(f)+frac{T_{(j+1,k+1)}(f)-T_{(j,j+k-1)}(f)}{left(frac{h_j}{h_{j+k}}right)^2-1}$



Thank you in advance.







integration numerical-methods numerical-calculus






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 27 at 2:12







baxbear

















asked Jan 26 at 15:43









baxbearbaxbear

398




398












  • $begingroup$
    What are the trapezoidal and what the Simpson sums? Are these the diagonals? Is the difference that you want to estimate between trapezoidal sums?
    $endgroup$
    – LutzL
    Jan 26 at 17:15










  • $begingroup$
    I think/hope I added all the missing information.
    $endgroup$
    – baxbear
    Jan 27 at 2:12


















  • $begingroup$
    What are the trapezoidal and what the Simpson sums? Are these the diagonals? Is the difference that you want to estimate between trapezoidal sums?
    $endgroup$
    – LutzL
    Jan 26 at 17:15










  • $begingroup$
    I think/hope I added all the missing information.
    $endgroup$
    – baxbear
    Jan 27 at 2:12
















$begingroup$
What are the trapezoidal and what the Simpson sums? Are these the diagonals? Is the difference that you want to estimate between trapezoidal sums?
$endgroup$
– LutzL
Jan 26 at 17:15




$begingroup$
What are the trapezoidal and what the Simpson sums? Are these the diagonals? Is the difference that you want to estimate between trapezoidal sums?
$endgroup$
– LutzL
Jan 26 at 17:15












$begingroup$
I think/hope I added all the missing information.
$endgroup$
– baxbear
Jan 27 at 2:12




$begingroup$
I think/hope I added all the missing information.
$endgroup$
– baxbear
Jan 27 at 2:12










0






active

oldest

votes











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3088392%2fromberg-integration-relative-error%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3088392%2fromberg-integration-relative-error%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

MongoDB - Not Authorized To Execute Command

How to fix TextFormField cause rebuild widget in Flutter

in spring boot 2.1 many test slices are not allowed anymore due to multiple @BootstrapWith