Printing a list of simultaneous equations
John- Don't try to forge a new wheel, when you can get one ready made and it might fit your wagon. Check out the `matlib` package on CRAN and devel on github: https://github.com/friendly/matlib install.packages("matlib") library(matlib) A <- matrix(c(1,2,3, -1, 2, 1), 3, 2) b <- c(2,1,3) showEqn(A, b) > showEqn(A, b) 1*x1 - 1*x2 = 2 2*x1 + 2*x2 = 1 3*x1 + 1*x2 = 3 > sound like what you want. Various vignettes illustrate this, also showing how to plot linear equations in 2D, 3D. browseVignettes("matlib")
On 1/18/2019 7:02 AM, Sorkin, John wrote:
I am trying to print a list of equations in an easily readable form. At this time all I can get is a series of characters enclosed in quotation marks rather than equations with numbers and equal signs. What I get is
y equalsigns x z
eq1 "0.5" "=" "1" "2"
eq2 "4" "=" "2" "3"
When what I want is
y x z
eq1 0.5 = 1 2
eq2 4.0 = 2 3
I am enclosing my R code below:
# Create matrix of coefficients of independent variables.
a <- matrix(c(1,2,2,3),nrow=c(2,2),byrow=TRUE)
dimnames(a)<-list(c("eq1","eq2"),c("x","z"))
cat("Matrix of independent variables\n")
a
# Create vector of dependent variables.
b <- matrix(c(0.5,4.0),nrow=c(2,1))
dimnames(b)<-list(c("eq1","eq2"),c("y"))
cat("Vector of dependent variables","\n")
b
cat("System of equations to be solved")
equalsigns <- c("=","=")
cbind(b,equalsigns,a)
Thank you,
John
John David Sorkin M.D., Ph.D.
Professor of Medicine
Chief, Biostatistics and Informatics
University of Maryland School of Medicine Division of Gerontology and Geriatric Medicine
Baltimore VA Medical Center
10 North Greene Street
GRECC (BT/18/GR)
Baltimore, MD 21201-1524
(Phone) 410-605-7119
(Fax) 410-605-7913 (Please call phone number above prior to faxing)
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Michael Friendly Email: friendly AT yorku DOT ca Professor, Psychology Dept. & Chair, ASA Statistical Graphics Section York University Voice: 416 736-2100 x66249 Fax: 416 736-5814 4700 Keele Street Web: http://www.datavis.ca | @datavisFriendly Toronto, ONT M3J 1P3 CANADA