K>> sparse(b)
ans =
(1,1) 3.3800
(1,2) -7.6031
(1,3) 1.7736
(1,4) 2.7026
(1,5) -0.8078
(1,6) -2.3500
(1,7) 3.3938
(1,8) -1.0400
(1,9) 5.8375
(1,10) 5.4809
(1,11) 5.6437
(1,12) 0.2300
(1,13) 0.3310
(1,14) -1.1580
(1,15) -0.0240
(1,16) -0.0240
(1,17) 0.1490
(1,18) -0.2622
(1,19) -1.4895
(1,20) -0.2810
(1,21) -0.1400
(1,22) 0.1110
(1,23) -0.5050
(1,24) -0.2960
(1,25) 1.1370
(1,26) -0.9640
(1,27) 1.0000
(1,28) 4.6700
(1,29) 5.9813
(1,30) 12.1000
(1,31) 2.3400
(1,32) 3.7200
(1,33) 3.3000
(1,34) 1.8500
(1,35) 4.1000
(1,36) 5.0000
(1,37) 0.3700
(1,39) 0.4500
(1,40) 1.6500
(1,41) 4.0000
(1,42) 4.0000
(1,43) 1.1600
(1,44) 12.9200
(1,45) 7.0000
(1,46) 5.5300
(1,47) -0.0153
(1,48) -0.0138
(1,49) -0.0045
(1,50) -0.0045
(1,51) -0.0184
(1,52) -0.0139
(1,53) -0.0189
(1,54) -0.0155
(1,55) -0.0166
(1,56) -0.0303
(1,57) -0.0186
(1,58) -0.0258
(1,59) -0.0101
(1,60) -0.0081
(1,61) -0.0160
(1,62) -0.3628
(1,63) -0.2927
(1,64) 0.5000
(1,65) 0.0800
(1,66) -0.0102
(1,67) -0.0102
(1,68) -0.0380
(1,69) -0.0119
(1,70) -0.0000
(1,71) -1.2000
(1,72) -0.9600
(1,73) -1.5300
(1,74) -0.5750
(1,75) -1.4971
(1,76) -4.9470
(1,77) -0.7981
(1,78) -0.4500
(1,79) -0.6882
(1,80) 0.0000
(1,81) 0.0000
(1,82) 0.0000
(1,83) -0.6100
(1,84) -0.6900
(1,85) -0.1400
(1,86) -2.1800
(1,87) 0.0000
(1,88) 0.0000
(1,89) -0.5600
(1,90) -0.2800
(1,91) 0.0000
(1,92) 0.0130
(1,93) -0.1960
(1,94) -0.2620
(1,95) 0.0000
(1,96) 0.5183
(1,97) 0.0000
(1,98) -0.0000
(1,99) -1.6920
(1,100) -10.3057
(1,101) 0.0000
(1,102) 2.1481
(1,103) 0.9076
(1,104) 0.0000
(1,105) -0.0145
(1,106) 3.3312
(1,107) -0.7495
(1,108) -0.7148
(1,109) -0.0018
(1,110) -0.0717
(1,111) -0.8500
(1,112) -0.0183
(1,113) 0.0000
(1,114) -0.0000
(1,115) -2.9990
(1,116) -2.7404
(1,117) 0.6876
(1,118) -0.6950
(1,119) -2.3278
(1,120) -0.4181
(1,121) -1.1528
(1,122) 10.5391
(1,123) 10.3501
(1,124) 14.7689
(1,125) -7.9436
(1,126) -0.3500
(1,127) -0.4100
(1,128) -0.3715
(1,129) -0.3586
(1,130) 0.2100
(1,131) -0.3554
(1,132) -1.7600
(1,133) 2.7992
(1,134) -4.2800
(1,135) 0.0000
(1,136) -4.4800
(1,137) 2.3100
(1,138) 0.0000
(1,139) 0.6600
(1,140) 0.0893
(1,141) -0.2900
(1,142) -0.0000
(1,143) -0.0227
(1,144) 0.0000
(1,145) -0.2694
(1,146) -0.9000
(1,147) -3.5300
(1,148) -0.9108
(1,149) -0.0213
(1,150) 0.0000
(1,151) -0.2800
(1,152) -0.4600
(1,153) 0.0000
(1,154) -0.5800
(1,155) -0.4100
(1,156) 0.0500
(1,157) -0.1000
(1,158) -2.2700
(1,159) -0.6448
(1,160) -0.0000
(1,161) -0.6922
(1,162) -0.0000
(1,163) -0.0000
(1,164) 0.0000
(1,165) -0.2927
(1,166) -0.6068
(1,167) 0.9574
(1,168) 2.5306
(1,169) -0.5327
(1,171) -0.2732
(1,172) -0.1195
(1,173) -0.0460
(1,174) 1.0872
(1,175) -0.1820
(1,176) -5.3500
(1,177) -0.6928
(1,178) -0.9645
(1,179) -5.1933
(1,180) 0.0000
(1,181) 0.0000
(1,182) -0.0138
(1,183) 0.0000
(1,184) -0.3590
(1,185) -6.0332
(1,186) 1.2155
(1,187) -0.4855
(1,188) -0.5442
(1,189) 1.9025
(1,190) -1.9102
(1,191) -1.2350
(1,192) 0.0000
(1,193) -0.3300
(1,194) -0.0811
(1,195) 0.0000
(1,196) 0.0000
(1,197) -0.2650
(1,198) 0.0514
(1,199) 2.0030
(1,200) -0.7400
(1,201) -0.3036
(1,202) -0.0700
(1,203) 0.0991
(1,204) 0.0000
(1,205) 0.0000
(1,206) -0.0092
(1,207) -0.3895
(1,208) -0.2700
(1,209) -0.6984
(1,210) 0.0000
(1,211) -0.1200
(1,212) -0.0700
(1,213) 0.0091
(1,214) -0.2911
(1,215) -0.4700
(1,216) -1.9035
(1,217) -1.7300
(1,218) -4.0883
(1,219) -2.2300
(1,220) -0.9070
(1,221) -5.2173
(1,222) 1.8100
(1,223) -0.7700
(1,224) -0.2900
(1,225) 0.0001
(1,226) 0.0044
(1,227) -0.0026
(1,228) -0.0853
(1,230) -0.2033
(1,231) 0.0000
(1,232) -6.0687
(1,233) -0.7700
(1,234) -0.2100
(1,235) -0.0000
(1,236) -0.5500
(1,237) -0.9517
(1,238) -1.5500
(1,239) -0.3900
(1,240) -0.0000
(1,241) -0.9200
(1,242) -0.2200
(1,243) -1.0011
(1,244) -1.1600
(1,245) -0.5700
(1,246) 0.0000
(1,247) -0.4800
(1,248) -0.0000
(1,249) 0.0000
(1,250) -0.3950
(1,251) -0.3070
(1,252) -0.6300
(1,253) -0.1410
(1,254) 19.2601
(1,255) -7.7700
(1,256) -2.2841
(1,257) -3.8080
(1,258) 0.6796
(1,259) -1.6019
(1,260) -1.7262
(1,261) -4.2517
(1,262) -0.5498
(1,263) -0.1000
(1,264) -0.9862
(1,265) -1.7498
(1,266) -5.5706
(1,267) -0.6082
(1,268) -0.6246
(1,269) -3.1345
(1,270) -0.0086
(1,271) 0.0000
(1,272) 0.0000
(1,273) -0.7764
(1,274) 0.0000
(1,275) -1.9500
(1,276) 0.0000
(1,277) -2.4494
(1,278) -0.2206
(1,279) -1.8350
(1,280) -0.7780
(1,281) 5.8792
(1,282) 0.0100
(1,283) 0.0524
(1,284) 0.5878
(1,285) 0.1318
(1,286) -1.9398
(1,287) -0.8600
(1,288) -0.0335
(1,289) 3.3692
(1,290) 2.8180
(1,291) 0.0011
(1,292) -0.2000
(1,293) -1.0197
(1,294) -0.5631
(1,295) -2.5189
(1,296) -3.7462
(1,297) 2.2528
(1,298) -0.9209
(1,299) 0.0000
(1,300) -0.0271
(1,312) 0.1700
(1,313) 0.3030
(1,314) 0.3740
(1,315) 0.1400
(1,316) 0.0540
(1,317) -0.1730
(1,318) -0.0047
(1,319) 0.1382
(1,320) 0.2330
(1,321) -0.0250
(1,322) 0.0430
(1,323) 0.2050
(1,324) 0.0160
(1,325) -0.4070
(1,326) 0.6082
(1,327) 3.0114
(1,347) -0.0053
(1,348) -0.0064
(1,349) -0.0016
(1,350) -0.0016
(1,351) -0.0064
(1,352) -0.0048
(1,353) -0.0065
(1,354) 0.0116
(1,355) -0.0058
(1,356) -0.0100
(1,357) -0.0064
(1,358) -0.0089
(1,359) -0.0035
(1,360) -0.0028
(1,361) -0.0052
(1,363) -0.0573
(1,366) -0.0035
(1,367) -0.0035
(1,368) -0.0125
(1,369) 0.0539
(1,370) 7.1002
(1,371) 0.6862
(1,372) -0.3990
(1,374) -0.0375
(1,375) -0.0896
(1,376) 5.8563
(1,377) -0.1405
(1,378) -0.0680
(1,379) 0.0377
(1,380) 0.0420
(1,381) 0.2516
(1,382) 3.1914
(1,383) -0.1950
(1,384) 0.