gnu: Add r-graphlayouts.

* gnu/packages/cran.scm (r-graphlayouts): New variable.

gnu/packages/cran.scm

@@ -15273,3 +15273,30 @@ (define-public r-systemfonts
 provides bindings to the native libraries for finding font files that can then
 be used further by e.g. graphic devices.")
     (license license:expat)))
+
+(define-public r-graphlayouts
+  (package
+    (name "r-graphlayouts")
+    (version "0.5.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (cran-uri "graphlayouts" version))
+       (sha256
+        (base32
+         "03dizbhhdhnzbj2i5zvqgs617kwcv4h2pha4f16adic0fph1rxl3"))))
+    (properties `((upstream-name . "graphlayouts")))
+    (build-system r-build-system)
+    (propagated-inputs
+     `(("r-igraph" ,r-igraph)
+       ("r-rcpp" ,r-rcpp)
+       ("r-rcpparmadillo" ,r-rcpparmadillo)))
+    (home-page "https://github.com/schochastics/graphlayouts")
+    (synopsis "Additional layout algorithms for network visualizations")
+    (description
+     "This package provides several layout algorithms to visualize networks
+which are not part of the igraph library.  Most are based on the concept of
+stress majorization by Gansner et al. (2004)
+<doi:10.1007/978-3-540-31843-9_25>.  Some more specific algorithms allow to
+emphasize hidden group structures in networks or focus on specific nodes.")
+    (license license:expat)))